Scalable semitransparent organic solar cells with robust film thickness tolerance for building-integrated photovoltaics

Domain: chemistry
Published: 2026-02-18
Editorial outcome: minor_revision

Abstract
Building-integrated photovoltaics (BIPVs) is a promising application for semitransparent organic solar cells (ST-OSCs). However, conventional ultra-thin (<80 nm) active layers for ST-OSCs, while balancing transmittance and efficiency, limit the cell-to-module efficiency remaining ratio (CTM) below 56%. Here, we achieve high semitransparency and efficiency in ST-OSCs with reasonable active layer thickness by manipulating the aggregation of acceptors in various donor-diluted blends processed with non-halogen solvent in ambient air. Using PM6:Qx-p-4Cl as a model system, we elucidate a unique film-formation mechanism and charge generation process, demonstrating that the fiber network and suitable aggregation size are crucial for ensuring higher performance in donor-diluted ST-OSCs. The 1 cm2 donor-diluted ST-OSCs with active layer thicknesses of 119 and 301 nm exhibit light utilization efficiencies (LUEs) of 4.04% and 3.02%, respectively. Notably, a 100 cm2 module demonstrates a CTM ratio of ~85% and a LUE of 3.32%, owing to its high film thickness tolerance, setting a new benchmark for large-area semitransparent modules. Furthermore, we demonstrate the feasibility of BIPVs in terms of power generation, energy storage, and temperature control through a scale-down model with a 600 cm2 power-generating window. These results reveal promising prospects for ST-OSCs in real-world applications.

Introduction
Building-integrated photovoltaics (BIPVs) are pivotal for revolutionizing sustainable urban architecture, with semitransparent photovoltaics emerging as an essential technology to realize this vision through transforming conventional building envelopes from passive energy consumers into self-powered structures. Organic solar cells (OSCs) emerge as promising candidates for semitransparent photovoltaics due to their unique benefits of optical bandgap regulation and the intrinsic semitransparency of the acceptor, thus demonstrating considerable potential for BIPVs.1–7 The development of BIPVs focuses on semitransparent properties, device efficiency, and large-area module processing technology for semitransparent organic solar cells (ST-OSCs).8,9 Specifically, the key driver in the preparation of high-performance BIPVs is realizing an optimal balance between average visible transmittance (AVT) and power conversion efficiency (PCE) in large-area semitransparent modules (ST-modules).

Compared to opaque OSCs, the performance of ST-OSCs is commonly evaluated using light utilization efficiency (LUE), which reflects the trade-off between AVT and PCE (LUE=PCE×AVT).10–12 A comprehensive analysis of reported data reveals two primary approaches to enhancing LUE. The first strategy involves optimizing film thickness, where researchers have systematically demonstrated that preparing an ultra-thin active layer (<80 nm) can overcome the LUE limitations for ST-OSCs.8,12–20 The second strategy focuses on further modulating the donor-to-acceptor ratio (D:A ratio) in thin films. Given that the visible absorption in high-performance organic photovoltaic systems predominantly originates from donor materials, diluting donor content effectively enhances the AVT but significantly reduces PCE.14,21 Notably, both strategies maintain the optimal LUE threshold at approximately 60–80 nm film thickness by utilizing harmful halogenated solvents (e.g., chloroform and chlorobenzene) in nitrogen-filled glovebox. Such ultra-thin active layer faces three critical obstacles in large-scale manufacturing: (1) exacerbated performance degradation when scaling up production, (2) significant biotoxicity of halogenated solvents and (3) critically low production yields resulting from stringent thickness control demands, which were not taken into full consideration in previous reports.

To quantitatively evaluate the performance loss during upscaling for OSCs, the cell-to-module efficiency remaining ratio (CTM) is proposed, which is calculated from the ratio of performance between the monolithic device and the corresponding large-area module.22,23 Impressively, the CTM of ST-OSCs is generally lower than that of opaque OSCs. Especially for the ST-module with an area above 100 cm2, the reported CTM of the 100 cm2 ST-module is around 56%, which lags far behind the 100 cm2 opaque module reported in previous works (~88%).23,24 In addition to inherent electric and geometric losses of the module design, this performance gap primarily stems from the increased active layer thickness during scaling up production, which reflects the fundamental challenge of fabricating very thin film using scalable fabrication technologies. However, the large active layer thickness leads to enhanced recombination, poor charge extraction, and reduced transmittance, resulting in exacerbated degradation of LUE for ST-OSCs.25,26 Consequently, it is necessary to optimize the AVT of the thick-film active layer and improve the film thickness tolerance for preparing high-performance upscaling ST-modules.27 In principle, it is recognized that the donor-dilution strategy is an efficient strategy for ensuring high transmittance in the thick active layer.5,17,28 However, the unsatisfactory D:A ratio remains challenges of the excessive aggregation and disordered structure for the non-fullerene acceptor, leading to imbalanced charge transport and competition between charge extraction and recombination.24,29,30 Recently, our group found that the optimal D:A ratio of the slot-die-coated device (1:1) shows a higher acceptor proportion than that of the spin-coated device (2:1) in some systems.31 This finding inspires us to consider that the combination of donor-dilution strategy and slot-die coating would represent a promising approach for improving CTM during large-scale production of ST-OSCs and provide new access to realize high-performance BIPVs.

Herein, we achieved high-performance thick-film slot-die-coated ST-OSCs by systematically manipulating the morphology of donor-diluted film (D:A ratio = 1:3) processed with non-halogen solvent in ambient air, and then obtained an excellent CTM in ST-modules for the demonstrated application under outdoor conditions. First, a high LUE of 4.04% with PCE of 10.57% and AVT of 38.21% are obtained in the 1 cm2 slot-die-coated semitransparent device (ST-device, D:A ratio of 1:3) with an active layer thickness of 119 nm. Even when the thickness increases to 301 nm, which is three times more than that of previously reported results,8,12–20 the LUE remains high at 3.02%, demonstrating exceptional film thickness tolerance. Next, by tracking acceptor aggregation and excited state behavior, we elucidate the unique aggregation mechanism and charge generation process in donor-diluted slot-die-coated bulk heterojunction (BHJ). Finally, the 100 cm2 printed ST-module prepared by the donor-dilution strategy yields a LUE of 3.32% and a CTM of around 85%. When transitioning from the laboratory to the outdoor environment, we utilized a scale-down house model with a 600 cm2 power-generating window (six modules in parallel) to demonstrate the feasibility of BIPVs in terms of power generation, energy storage and temperature control. Overall, our work elevates the performance of upscaling ST-OSCs to a higher level and highlights the potential of donor-diluted ST-devices for real-world applications.

Results
Photovoltaic properties
The chemical structures of the PM6:Qx-p-4Cl system and thickness-normalized absorption spectra of the blends with different D:A ratios are illustrated in Fig. 1a, b. To investigate the photovoltaic properties of spin-coated and slot-die-coated devices with different D:A ratios processed with non-halogen solvent in ambient air, the PCE versus D:A ratios of large-area opaque devices (1 cm2) based on PM6:Qx-p-4Cl is presented in Fig. 1c and Supplementary Fig. 1. And the corresponding EQE spectra are shown in Supplementary Fig. 6. The optimal D:A ratio of the spin-coated device is centered at 1:1.5 (Supplementary Table 2). The corresponding device shows PCE of 13.80%, along with open-circuit voltage (VOC) of 0.89 V, short-circuit current density (JSC) of 21.29 mA cm-2 and FF of 72.61%. For the devices fabricated by slot-die coating with 90 °C coating substrate, the large-area device based on PM6:Qx-p-4Cl exhibits the highest PCE of 12.79% at D:A ratio of 1:3, indicating that the slot-die coating method can realize better performance in donor-diluted devices. Besides, we summarized the photovoltaic parameters of PM6:Y6, PM6:L8-BO, and PM6:Qx-1 with different D:A ratios in Supplementary Fig. 2–9 and Supplementary Table 3–5. All the slot-die-coated systems show high performance at a high acceptor ratio. In particular, the PM6:Y6 devices achieve the optimal efficiency when the acceptor ratio exceeds twice that of the donor. However, the best performance of PM6:L8-BO and PM6:Qx-1 devices is obtained at D:A ratios of 1:1.7 and 1:1.5, respectively. Further dilution of donor content leads to a decline in device performance.

Benefiting from the lower donor content at optimal D:A ratio of PM6:Qx-p-4Cl, we further explore the photovoltaic properties of ST-OSCs. A 20 nm ultra-thin Ag electrode is utilized to fabricate the slot-die-coated large-area ST-devices. As seen in Fig. 1b–d and Supplementary Fig. 11, diluting donor content within the active layer significantly reduces the absorption in the visible range, realizing high AVT in donor-diluted ST-OSCs. The highest PCE is obtained at D:A ratio of 1:3 with AVT of 15.43%, which is consistent with the corresponding opaque devices (Supplementary Table 6-7). As shown in Fig. 1e, Supplementary Fig. 13, and Supplementary Table 8, we compared the AVT of 1:1.5 and 1:3 active layers with different thicknesses. The AVT of donor-diluted blends (D:A=1:3) is significantly higher than controls (D:A=1:1.5) at the same film thickness. More importantly, the donor-diluted blend with a large thickness (205 nm) exhibits a high AVT of 54.68%. However, achieving an AVT above 50% requires a thickness below 100 nm for the 1:1.5 blend. With increasing film thickness, the advantage in transmittance of donor-diluted blends becomes more pronounced. The parameter Δd quantifies the thickness difference between 1:1.5 and 1:3 blends under constant AVT. At AVT of around 70%, Δd is around 80 nm. For thicker blends, Δd is increased to above 125 nm at AVT around 55%. These results suggest that the integration of donor dilution and slot-die coating is a viable method for the mass production of high-performance ST-OSCs, exhibiting high AVT in thick films.

To further improve the photovoltaic and semitransparent properties, we adopted a conventional device structure, and a 35 nm MoO3 anti-reflective coating (ARC) layer was coated on an ultra-thin Ag electrode.2,8,18,32,33 The current density (J)-voltage (V) curves and detailed parameters of ST-OSCs with ARC layer are presented in Fig. 1f, Supplementary Fig. 1 and Supplementary Table 6. The corresponding EQE spectra are shown in Supplementary Fig. 10. The slot-die-coated ST-device with a small active layer area (0.0256 cm2) yields a VOC of 0.87 V, JSC of 19.85 mA cm-2, FF of 71.66% and PCE of 12.37%. For large-area ST-OSCs with different thicknesses, the 1 cm2 device with 180 nm active layer shows the highest PCE of 11.81%, along with a VOC of 0.89 V, JSC of 18.86 mA cm-2 and FF of 70.32%. When the active layer thickness is increased to 301 nm, the PCE is slightly reduced to 11.25%. It is worth noting that the introduction of ARC improves the AVT of thick-film ST-devices to more than 30% (Fig. 1g and Supplementary Figs. 10–12), indicating outstanding optical behaviors as shown in Supplementary Fig. 14.

The parameter of LUE is calculated to reveal the balance between PCE and AVT.1,10,20 The LUE of 4.00% is achieved in a small-area device. Besides, Fig. 1h and Supplementary Table 1 summarize the LUE values of reported large-area ST-OSCs with different thicknesses. The high LUE above 3% is mostly achieved by decreasing the active layer thickness to below 90 nm. Increasing thickness leads to a significant drop in the transmittance of the undiluted devices (Fig. 1e), thereby reducing the LUE to around 2% or even below 1.5% for large-area ST-OSCs with thicknesses larger than 100 nm. In contrast, the high carrier mobility (μ) of the Qx-p-4Cl system (μhole = 6.95×10-4 cm2 V-1 s-1, μelectron = 5.79×10-4 cm2 V-1 s-1) ensures high efficiency in thick-film devices as presented in Supplementary Fig. 15. Importantly, as the thickness increases from 119 nm to 301 nm, the LUE of the PM6:Qx-p-4Cl-based donor-diluted device decreases from 4.04 to 3.02%, exhibiting remarkable thickness tolerance. As far as we know, the 1 cm2 ST-devices with 119 nm thickness fabricated in this work could be listed as one of the high-performing large-area ST-OSCs in terms of high LUE.

Film morphology and photophysics characteristics
The investigation of film morphology is crucial to understanding the device performance. First, grazing incident wide-angle X-ray scattering (GIWAXS) technology was performed to study the multiscale morphological evolution.34–36 As shown in Fig. 2a and Supplementary Fig. 16–17, all the BHJ blends prefer face-on orientation due to the strong (010) signal along the out-of-plane (OOP) direction.35,37,38 The parameters of crystalline coherence length (CCL) and π-π stacking distance (d) were extracted from GIWAXS patterns to gain deeper insight into molecular packing behaviors.36,38,39 The calculated results are presented in Fig. 2b and Supplementary Table 9. The spin-coated films exhibit an elevated CCL of the (010) π-π stacking peak in the OOP direction with increasing acceptor content. The CCL of spin-coated films with 1:0.5, 1:1.5, and 1:3 D:A ratios are 25.25, 27.81, and 30.41 Å, respectively, attributed to the excessive crystallinity in the 1:3 ratio film.40,41 Meanwhile, a similar trend is observed in slot-die-coated films, but the CCLs of slot-die-coated films with different D:A ratios are lower than in spin coating cases overall. It can be seen that the donor-diluted slot-die-coated film has more reasonable crystallinity relative to the spin-coated film.

In addition, atomic force microscopy (AFM) was carried out to gain the surface morphological characteristics as shown in Fig. 2c and Supplementary Fig. 18-21.42–44 The aggregation of Qx-p-4Cl within spin-coated films is enhanced with increasing acceptor ratio, accompanied by improved root mean square (Rq) from 3.29 nm at 1:0.5 to 8.57 nm at 1:3 as presented in Supplementary Table 10. An excessive aggregation of Qx-p-4Cl is shown in the spin-coated film with 1:3 ratio, which is consistent with the results of GIWAXS. For slot-die-coated films, all the films with different D:A ratios exhibit consistent surface morphology with lower Rq than spin-coated films. Notably, the obvious fibril-like structure with fibril width in the range of 20-21 nm can be observed even at an extreme D:A ratio (1:5), and diluting donor content has a negligible effect on fibril size as shown in Supplementary Fig. 19. Combined with the GIWAXS results, the appearance of excessive crystallinity-induced aggregation in the donor-diluted spin-coated film (1:3) can lead to inferior device performance.40,41 On the contrary, all the slot-die-coated films exhibit more reasonable molecular packing features and fiber network structure at different D:A ratios, which ensures efficient charge transport. These results may be related to the different aggregation process of the acceptor from spin coating.

According to previous reports, the morphology has been proven to determine the behaviors of the excited state within the active layer. Thus, the transient absorption (TA) spectra of spin- and slot-die-coated films were recorded to investigate the excited state kinetics.45–48 The 800 nm pump pulse was utilized to selectively excite the Qx-p-4Cl phase individually. As shown in Fig. 2d, e and Supplementary Fig. 23–24, the rises of excited state absorption (ESA) signals located at around 875 and 950 nm are observed, corresponding to local excitation states (LEs) and polarons, respectively. Meanwhile, the ground-state bleaching (GSB) signal among the absorption range of PM6 donor emerges together with the decay of LEs ESA signal, which is assigned to the hole transfer process.46,48 Fig. 2f shows the kinetic decay curves for spin-coated films, revealing that increasing the acceptor content suppresses the hole transfer process, as evidenced by a progressive lengthening of the rise time of the PM6 GSB signal. As summarized in Supplementary Table 11, the half-time of rise (trise,half-time) for the GSB signal increases from 0.39 ps in the 1:0.5 blend to 0.50 ps in the 1:1.5 blend and further to 0.61 ps in the 1:3 blend. The early-stage lifetime of the LEs kinetic trace is also extracted to assess the dissociation of excitons, as shown in Supplementary Table 12, and the fitted lifetime grows from 0.29 in the 1:0.5 blend to 0.58 ps in the 1:3 blend. This prolonged LE lifetime implies that excitons remain localized for a longer duration before dissociating. Besides, the increased acceptor content in the spin-coated blend can accelerate the charge decay as the polaron signal of the blend with higher acceptor content shows more rapid decay (Fig. 2f and Supplementary Table 13).49 For slot-die-coated films, Fig. 2g demonstrates that highly efficient charge generation is achieved across all D:A ratios. The corresponding trise,half-time values fall within a narrow range of 0.27–0.36 ps, which is comparable to that of the non-diluted films fabricated with spin coating. Similarly, the polaron signal dynamics show consistent behavior across different ratios, further confirming the robustness of charge generation and transport in slot-die-coated films. The underlying mechanism for these divergent behaviors is elucidated through AFM analysis. For spin-coated films, the extreme D:A ratio in donor-diluted film results in large phase aggregation of acceptor (Fig. 2c), leading to insufficient donor/acceptor interface, which severely hampers exciton dissociation and charge transfer. Meanwhile, the loss of the interconnected network is responsible for the limitation in charge transport for donor-diluted films. In contrast, the more ideal morphology with prominent fibrous features in slot-die-coated films with different D:A ratios ensures an efficient and nearly identical charge transfer process and charge transport, indicating that the donor dilution strategy has a negligible effect on excited state dynamics in PM6:Qx-p-4Cl slot-die-coated films.

As shown in Supplementary Fig. 19-22, and Supplementary Fig. 26, we quantified the exciton diffusion length (LD) and fibril width of slot-die-coated films to verify the above conclusions.50–55 The calculated LD values are listed in Supplementary Table 14-15.56–59 It is evident that the fibril widths in all the slot-die-coated PM6:Qx-p-4Cl films are similar (~21 nm), and the larger LD of Qx-p-4Cl (22.34 nm) enables efficient exciton dissociation, as confirmed by a photoluminescence quenching efficiency (PLQE) above 90% (Supplementary Fig. 27). The fibril widths of PM6:Y6 films with different D:A ratios are nearly identical (~24 nm), leading to similar exciton dynamics as shown in time-resolved photoluminescence (TRPL) measurement (Supplementary Fig. 25, Supplementary Fig. 28–29, and Supplementary Table 16). In contrast, for L8-BO- and Qx-1-based systems, a slight increase in fibril width is observed with donor dilution, indicating reduced D/A interface and suppressed exciton dissociation in donor-diluted blends. These results are consistent with performance characteristics.

Combining the above results, we believe that the outstanding performance in donor-diluted slot-die-coated devices mainly originates from the nearly-identical morphology and excited state dynamics at different D:A ratios. To figure out the internal reason, the film-forming kinetics were investigated by in-situ UV-Vis spectrum technology.35,36,44,60,61 Fig. 3a plots the original in-situ UV-Vis spectra of spin-coated and slot-die-coated films with different D:A ratios. And the corresponding absorption line profiles are shown in Fig. 3b, c, revealing processes of film-forming and material aggregation. For spin-coated BHJ films, the entire film-forming process can be divided into two stages, which are differentiated by dashed lines.43,60,62 Stage 1 shows a decrease in peak intensity and a slow red shift of peak location during the quick solvent removal, which represents the process of thinning of the liquid film as the solvent evaporates. In stage 2, a distinct increase in peak intensity and a rapid red shift of the peak location are observed, indicating the aggregation of Qx-p-4Cl within a supersaturated film. Subsequently, the absorption signal of Qx-p-4Cl becomes stable, indicating that the film has completed the transition from liquid to solid.

The schematic diagram in Fig. 3d clearly shows the detailed film-formation process. We focused on the duration of stages 1 and 2 to investigate the behavior of acceptor aggregation during the film-forming process. First, the spin-coated films with D:A ratios of 1:0.5, 1:1.5, and 1:3 exhibit obvious differences in stage 1, corresponding to durations of approximately 9.5, 5.7, and 3.5 s, respectively. This difference is associated with solution viscosity, which is listed in Supplementary Table 18. Diluting donor content reduces the viscosity of the BHJ solution from 5.95 mPas at D:A ratio of 1:0.5 to 1.85 mPas at 1:3, accelerating the process of the liquid film reaching supersaturation.63 In stage 2, although all the spin-coated films show a similar duration of around 0.7 s, the film with higher acceptor content displays a larger red shift of the Qx-p-4Cl absorption peak. The films with 1:0.5, 1:1.5 and 1:3 ratios undergo the red shift to around 793, 800 and 806 nm, respectively, suggesting that increasing acceptor content can enhance the crystallinity-induced aggregation of acceptor during stage 2. For slot-die-coated films, those with different D:A ratios exhibit a similar duration of the entire film-forming process of around 1.7 s, which is more rapid than that of spin-coated films due to the high temperature of the coating substrate. In the initial stage, increasing acceptor content shortens the corresponding duration despite a subtle difference. The durations of stage 1 for slot-die-coated films with 1:1, 1:3, and 1:5 ratios are 1.1, 0.7, and 0.5 s, respectively. When the film-forming process reaches stage 2, the corresponding duration times for all the slot-die-coated films are around 0.5 s, and their red shifts are almost identical, indicating a negligible influence of the D:A ratio on the aggregation of the acceptor. This is mainly because the hot substrate during slot-die coating can eliminate the excessive aggregation of the acceptor.64 Subsequently, there is a distinct reduction in peak intensity and slow red shift of peak location after stage 2 in 1:3 and 1:5 films, which is marked as stage 3. It represents the further thinning of the active layer, followed by the formation of a solid film. Notably, during slot-die coating, the solvent evaporation is accompanied by lateral solution diffusion across the substrate, which is fundamentally different from spin coating. This lateral spreading results in continuous thinning of the liquid film. This behavior is significantly governed by viscosity. Low viscosity enhances the molecular diffusion and reduces solvent diffusion resistance, thereby prolonging the diffusion time. Conversely, high viscosity restricts diffusion dynamics.65 As shown in Supplementary Table 18, the PM6:Qx-p-4Cl solutions with 1:1, 1:3, and 1:5 exhibit viscosity of 3.55, 1.85, and 1.44 mPas, respectively. The reduced viscosity prolongs the solution diffusion process, which directly accounts for the emergence and extended duration of stage 3 observed in donor-diluted slot-die-coated blends. Notably, the 1:5 blend exhibits a longer stage 3 duration (0.7 s) compared to the 1:3 blend (0.4 s), attributed to its lower viscosity, which enhances lateral spreading and delays film solidification. More importantly, the emergence of stage 3 in the 1:3 and 1:5 slot-die-coated films demonstrates that acceptor aggregation occurs within the liquid film rather than in a supersaturated state. As illustrated in Fig. 3d, this liquid-phase aggregation enables the formation of well-defined fibrillar structures and continuous percolating networks.64,66,67 However, the low viscosity may induce Marangoni flows during natural drying, influencing the film continuity and morphology of the active layer.36 To avoid this issue, we adopted an airflow-assisted method to reduce the temperature gradient, thereby suppressing Marangoni flows and the coffee ring effect. These results comprehend why the ideal morphology and efficient charge generation can be achieved in slot-die-coated donor-diluted film.

Optimization of slot-die-coated semitransparent modules
To highlight the superiority of high film thickness tolerance in preparing ST-modules, we further enlarged the active layer area to around 100 cm2, which is formed from 23 sub-cells with an active layer area of 4.365 cm2 as shown in Fig. 4a and Supplementary Fig. 32. The inverted device structure of indium tin oxide (ITO)/zinc oxide nanoparticle (ZnONP)/active layer/MoO3/Ag/MoO3 is employed for module fabrication. Thermal evaporation is used to deposit the MoO3 interlayer and top Ag electrode to enable precise control of film thickness.68 Because the efficiency and transmittance of ST-OSCs are highly sensitive to film thickness.7 To minimize the performance degradation caused by geometric loss, P1, P2, and P3 were laser scribed.69–72 The width of the sub-cell is 4.5 mm and the length between P1 and P3 is 174 μm, thus showing a high geometric fill factor (GFF) of 96.28%. As shown in Fig. 4b and Supplementary Table 17, the 100 cm2 ST-module exhibits PCE of 10.40% with VOC of 18.85 V, JSC of 0.79 mA cm2 and FF of 69.85%. Supplementary Fig. 30-31 present the corresponding transmittance curve and color coordinate in the CIE-1931 chromaticity diagram. The 100 cm2 ST-module shows AVT of 31.97% and color rendering index (CRI) of 85%, yielding an LUE of 3.32%. Supplementary Fig. 33 and Supplementary Table 19 summarize the LUE values of reported large-area ST-modules. It is worth noting that the LUE value of 100 cm2 ST-OSCs prepared in this work demonstrates strong competitiveness compared to other reported ST modules.

Figure 4c summarizes the CTM of LUE (CTMLUE) of ST-modules reported in recent works. It is found that the CTM values of reported ST-modules are generally low, especially in 100 cm2 modules (<60%), due to the large difference in film thickness between monolithic devices and module devices in ST-OSCs. Impressively, the 100 cm2 ST-module fabricated in our work yields a CTMLUE of 83.00% relative to a small-area ST-device, which is nearly 1.5 times that of other reported 100 cm2 ST-modules and is comparable to that of reported mini ST-modules (<20 cm2).24 When the large-area ST-device (180 nm) is taken as the reference, the ST-module shows CTMLUE of 85.13%. Besides, similar results are also found in the summary of CTM of PCE (CTMPCE). As shown in Supplementary Fig. 34 and Supplementary Tables 20–21, the 100 cm2 ST-module shows a CTMPCE of 84.07% relative to small-area ST-OSC and 88.06% relative to the large-area ST-OSC (180 nm), respectively. It is revealed that the high thickness tolerance improves the CTMPCE of ST-module to a level comparable to opaque modules (84%-88%) and significantly suppresses the performance loss during upscaling for ST-OSCs. High film thickness tolerance can enable CTM approaching 90% for ST-module, eliminating the gap with opaque modules.

Considering the practical application of ST-OSCs, most reports reflect the optical characteristics of ST-OSCs, such as greenhouse, temperature control, etc.5,24 The power-generating functionality is rarely considered. To comprehensively exhibit the potential application of ST-modules in BIPVs, we verified their feasibility from the perspectives of photovoltaic properties and optical properties as shown in Fig. 4d. For photovoltaic application, six encapsulated 100 cm2 modules were connected in parallel as a whole power-generating window (around 600 cm2 in total) to achieve image display and energy storage, which are common and necessary application scenarios in homes and offices. Supplementary Fig. 35 provides the block diagrams of driving a liquid crystal display (LCD) screen and charging the 18650 lithium-ion battery system through the semitransparent power-generating window, which is integrated into a scaled-down house model (Fig. 4e). When the model is transferred to the sunny outdoor environment, we utilize the 600 cm2 power-generating window to simultaneously power a 4.3” LCD and a lithium-ion battery. It is worth noting that the screen can display artistic images when the VGA video signal is connected to the LCD (Supplementary Fig. 36 and Supplementary Movie 1). On the other hand, the high acceptor content in the donor-diluted blend can absorb more near-infrared (NIR) light, thereby effectively blocking the NIR radiation and heat. The ST-module exhibits an excellent infrared radiation rejection (IRR) of 88.28%. As shown in Fig. 4f and Supplementary Fig. 37, another scale-down house model was exposed to the solar simulator to simulate the sunlight exposure. During the 30 min continuous irradiation, the temperature inside the house model covered with ST-module “window” is increased from ambient temperature (21.4 °C) to 26.5 °C. When the ST-module is withdrawn, a significant increase in temperature from 26.5 °C to 35.7 °C is observed after 30 min of irradiation. The detailed temperature data are listed in Supplementary Table 22. This increase is approximately twice that of the house model covered with ST-module window, indicating an excellent capability of temperature control of donor-diluted ST-modules. Combined with the application verification of power-generating functionality, these results demonstrate the feasibility of ST-OSCs in BIPVs.

Device stability is also a key concern in the application of ST-OSCs. The photostability of 1 cm2 donor-diluted ST-OSCs (D:A = 1:3) was tested under one sun illumination in a nitrogen atmosphere, as shown in Supplementary Fig. 38. The large-area device yields T90 (retains ca. 90% of the initial efficiency) approaching 1000 h and extrapolated T80 (retains ca. 80% of the initial efficiency) exceeding 3100 h, indicating excellent photostability in donor-diluted ST-OSCs. Furthermore, the outdoor stability testing for the 100 cm2 ST-module was conducted to simulate real-world operating conditions better, and the weather data during the testing period were summarized in Supplementary Table 23. When the ST-module was exposed to the outdoor environment for around 1000 h, the PCE dropped to 82.61% of its initial efficiency. It is worth noting that the extrapolated T80 of the ST-module was calculated to 1500 h. As a result, donor-diluted ST-OSCs, including monolithic devices and modules, yield high performance and long-term stability, demonstrating excellent potential for practical applications.

Methods
Materials
The polymer PM6 and non-fullerene acceptors Qx-p-4Cl, Y6, L8-BO and Qx-1 were obtained from Hyper, Inc (China). The electron transport layer PDINN was purchased from Solarmer Materials, Inc. The solvent o-xylene was purchased from Sigma-Aldrich Inc. The additive 1-chloronaphthalene (CN) was purchased from TCI. All the materials were used in this study without any purification. The large-area glass/ITO substrates were purchased from Youxuan New Energy Technology Co., Ltd.

Devices fabrication
The conventional device structure of ITO/PEDOT:PSS/active layer/PDINN/Ag was used in this work. The glass/ITO substrates with a sheet resistance of 15 Ω square-1 were cleaned in deionized water, acetone, ethanol, and isopropanol with ultrasonic treatment for 30 min. Afterward, the glass/ITO substrates were treated with ultraviolet–ozone (Ultraviolet Ozone Cleaner, Jelight Company, USA) for 15 min. PEDOT:PSS as the hole transport layer was spin-cast on ITO glass at 5000 rpm for 30 s. And then, the PEDOT:PSS-coated ITO substrates were baked at 150 °C for 15 min in air. The PM6:Qx-p-4Cl (the total concentration is 20 mg mL-1), PM6:Y6 (the total concentration is 16 mg mL-1), PM6:L8-BO (the total concentration is 17.6 mg mL-1) and M6:Qx1 (the total concentration is 20 mg mL-1), with different D:A ratios were dissolved in O-xylene solvent with 0.5 vol% CN, and stirred at 80 °C overnight. For spin-coated devices, the active layer was spin-coated on PEDOT:PSS layer with 3000 rpm and 30 s. For slot-die-coated devices, the active layer was slot-die-coated on the PEDOT:PSS layer with injection speed of 160 μL min-1, coating speed of 12 mm s-1 and coating temperature of 90 °C for slot-die-coated devices. Next, the PDINN (1 mg mL-1 in methanol) was spin-coated on the active layer with 3000 rpm and 30 s. Finally, the 100 nm Ag electrode was evaporated under vacuum condition with pressure of around 1.0×10-6 mbar for opaque devices. For ST-OSCs, the 20 nm ultra-thin Ag electrode and 35 nm MoO3 ARC were sequentially evaporated on the PDINN layer under vacuum condition with pressure of around 1.0×10-6 mbar.

Characterization
The photovoltaic characteristics of devices were measured in a N2-filled glovebox. The J-V curves were measured with Newport Thermal Oriel 91159A solar simulator under AM 1.5G condition, and the Newport Oriel PN 91150V Si-based solar cell was used to calibrate the light intensity. And the device area for large-area devices and modules are 1 and 100 cm2, respectively. Finally, the J-V curves were recorded by Keithley 2400 source-measure unit. More than 10 devices were fabricated to ensure the reproducibility of the data. Furthermore, the Oriel Newport system (Model 66902) was used to investigate the EQE of OSCs.

The space-charge-limited current (SCLC) method is adopted to calculate carrier mobility. For SCLC fitting, the Mott-Gurney law (J=9×ε0εrμV2=8×L3) is used, where εr is the permittivity of materials (εr of 3 is selected in this work), ε0 is the vacuum permittivity (8.854×10-12 F/m), and L is the film thickness (L of 100 nm is used in this work).

The femtosecond TA spectra were measured with the optical instrument consisting of a Ti:sapphire femtosecond laser (coherent) and an optical parametric amplifier (OPA) system. The seed pulses with 35 fs pulse width and a repetition rate of 1 kHz are generated from the amplified Ti:sapphire femtosecond laser, which can be split into two parts of laser. One for routing to the OPA to provide pump pulse, and the other for generating a broadband probe light. The energy of the pump beam was 18 nJ pulse-1, which is too low to generate the annihilation effects of exciton–exciton and exciton–charge. GIWAXS measurement was performed by XEUSS WAXS/SAXS system, Xenocs, France. The corresponding X-ray wavelength and incident angle are 1.5418 Å and 0.18°, respectively. And 2D scattering patterns were obtained by Pilatus 300K. AFM images were obtained from the devices directly on a VEECO Dimension 3100 atomic force microscope working under tapping mode. The film-formation process was conducted on a lab-assembled in-situ absorption test apparatus with an integrated Filmetrics F-20 spectrometer, and the absorption baseline was taken with glass/ITO/PEDOT:PSS before each coating session. For PL and TRPL measurements, the MAR 165 CCD detector with time-correlated single-photon counting (TCSPC) module was used to collect the data, and the pump wavelength is 800 nm.

The LD can be calculated via fluence-dependent photoemission kinetics. The effect of annihilation on the photoemission decay is described by Eq. (1).
dn(t) / dt = -kn(t) - γn2(t) (1)
where n(t), k and γ are the excitation density as a function of decay time t, and monomolecular decay constant and bimolecular recombination rate, respectively. And the γ can be obtained by fitting experimental data via Eq. (2).
n(t) = n(0)e-kt / (1 + γ n(0) / 2k [1 - e-kt]) (2)
where n(0) is the initial excitation density at t=0. And LD is calculated by LD = (Dτ), where τ is exciton lifetime and D is the diffusion coefficient, which is given by D=γ/(8πr) (r is the annihilation radius approximated as 2 nm).

The geometric fill factor (GFF) is defined as the ratio of the effective area of the module (Aeffectivearea) (i.e., the total active layer area of all the sub-cells) to the total module area (Amodulearea):
GFF = Aeffectivearea / Amodulearea = (n×l×W) / (n×l×(W+w)) = W / (W+w) (3)
where n and l represent the number of sub-cells and the length of sub-cells, respectively. The W is width of the sub-cell, and w is the the width of the dead area (i.e., the distance between P1 and P3).

The viscosity data were measured via a viscometer (Brookfield, DV2T).

Peer review rounds
[{"round": 1, "reviewer_comments": {"reviewer_1": "The authors realized excellent performance in large-area translucent devices with robust film thickness tolerance, revealing the promising application prospects of ST-OSCs. It is of significant interest that the practicality of BIPVs for power generation, energy storage, and temperature regulation has been confirmed through a scaled-down model featuring a 600 cm2 power-generating window. Besides, the unique aggregation mechanism and excited state dynamics in slot-die-coated donor-diluted blends were analyzed, which can support their conclusions. The manuscript is well organized and demonstrates the feasibility of ST-OSCs in BIPVs. I would like to recommend its publication in Nature Communications after minor revision.\n1. In Fig. 4c, the authors achieved high CTMLUE in this work, however, the detailed values are not mentioned in the manuscript nor listed in tables. The same issue is also observed in Supplementary Fig. 34. The author should provide corresponding detailed data. Additionally, please clarify the film thickness used for the CTMLUE calculation between the 1 cm2 device and the module.\n2. In Fig. 3c, why did stage 3 only appear in the donor-diluted slot-die-coated blends, while the slot-die-coated blend with 1:1 ratio shows the film-formation dynamic similar to the spin-coated blends? Interestingly, stage 3 is more pronounced in the blend with lower donor content, and the duration time of stage 3 becomes longer with diluting donor content. Can authors give more explanations?\n3. For AFM measurement, the authors point out that the change of D:A ratio has a subtle effect on the fiber network structure of slot-die-coated blends via detecting the surface morphology. Can D:A ratio affect the fiber size? The authors should provide some discussion on the microscopic scale.\n4. The change of D:A ratio can affect the absorption characteristics of bulk heterojunction blends; however, this work lacks absorption spectroscopy measurements of PM6:Qx-p-4Cl with different D:A ratios. The authors should include the relevant results and provide further discussion.\n5. Some minor mistakes should be proofed throughout the article: (1) The black data points in Fig. 1e are of different sizes; (2) The detailed temperature data in Fig. 4h should be listed in a table.", "reviewer_2": "In the manuscript, the authors have developed a new system, fabricated via slot-die coating with a non-halogen solvent in ambient air, that can maintain high light utilization efficiency (LUE) while showing exceptional film thickness tolerance from 100 to 300 nm. This development represents a substantial advancement for semi-transparent organic solar cells (ST-OSCs), which traditionally achieve high LUE at film thicknesses of less than 100 nm. Additionally, the authors utilized a scaled-down house model featuring a 600 cm² power-generating window to demonstrate the potential of BIPVs for power generation, energy storage, and temperature regulation, highlighting the promise of donor-diluted translucent devices for real-world applications. I suggest that the manuscript be accepted with minor revisions.\n1) Fig. 2 demonstrated both the mechanism behind the high-performance donor-diluted ST-OSCs and the generality of the donor-dilution strategy by employing a combination of TA technology, LD calculation, and multi-photovoltaic system comparative studies. In fact, there are some minor logical confusions here. Firstly, the excited state behaviors are closely related to morphology; however, this work discusses less about the influence of morphology on excited state dynamics. Secondly, the discussions in this section would benefit from phase domain size analysis, as the domain size and LD collectively affect whether exciton can reach the donor-acceptor interface. Additionally, in my opinion, the inclusion of the analysis of Eb here seems tangential to the main focus issue. Therefore, the authors need to reorganize the discussions in this section to improve the overall logic.\n2) There is insufficient discussion of TA spectroscopy in this article, especially for the hole transfer process. More discussions are needed. Importantly, this manuscript would be strengthened by including a comparison of the dynamics between spin-coated and slot-die-coated blends. In addition, the information on probe wavelength and pump wavelength is missing in Fig. 2f-g, which will confuse readers. The authors need to complete the relevant information.\n3) In the measurement of in-situ UV-Vis spectra, the authors proposed that the solution removal during film formation results in a drop in absorption intensity. However, the proposed explanation is inconsistent with the splashing-free nature of slot-die coating method, which distinctly differentiates it from spin coating. This manuscript should discuss alternative reasons for the absorption decrease in slot-die coating.\n4) The EQE, transmittance (T) and reflectance (R) spectra are necessary for the study of ST-OSCs. This article measured the EQE and transmittance spectra, but lacked the characteristics of the reflectance spectrum. The authors need to add the reflectance spectrum and the EQE+T+R spectrum in this article to support the results of device performance.\n5) The calculation method of GFF is missing. The authors need to add the information in the methods section.\n6) Closely related papers should be cited, such as Nat Commun 2025, 16, 7421; Adv. Mater. 2025, 37, 2420439; Adv. Funct. Mater. 2023, 33, 2212601.", "reviewer_3": "In their manuscript “Scalable Semitransparent Organic Solar Cells with Robust Film Thickness Tolerance for Building-Integrated Photovoltaics”, the authors present slot-die coated semitransparent organic solar cells and modules with high LUE. I find the topic relevant, but I think the following questions need to be addressed before the manuscript can be accepted in Nature Communications:\n• The authors speak of translucent cells and modules. Is this used with the same meaning as semitransparent, or is there a difference?\n• I do not completely understand the cell-to-module efficiency remaining ratio (CTM) that the authors introduce. Do they compare the efficiency of the semitransparent module the to the opaque cell? That would not be a fair comparison. If they compare the semitransparent cell with the semitransparent module, I do not understand why the values is so low.\n• How general is the difference between spin-coating and slot-die coating that is shown in Figure 1b? The authors have investigate the morphology and photophysics for different blends, have they also analyzed the device performance?\n• On page 3, the authors write that thin active layers face exacerbated performance degradation when up-scaled. Can they clarify what they mean by performance degradation, and give a reference for that?\n• Transmittance spectra and photographs of the cells are given in the Supporting Information, but not in the main text. I think they are relevant for the content of the manuscript and at least some of the spectra should be moved to the main manuscript. On the other hand, some of the details shown in Figure 4 could go to the Supporting Information.\n• If AVT values are given (for instance on page 5), the corresponding spectrum should be referenced.\n• The authors should perform a consistency check of EQE + Transmittance < 100% for at least some of the devices.\n• If I understand correctly, the slot-die coated modules were fabricated with an evaporated silver top electrode and MoO3 layer. The latter is not really convenient for large-area production. Can the authors comment on this?\n• Since the authors highlight the applications of semitransparent OPV, they should include operational stability of their modules.", "reviewer_4": "The manuscript reports a donor-dilution strategy for fabricating thick-film slot-die-coated ST-OSCs using non-halogenated solvents under ambient conditions. The authors demonstrate devices with high efficiency, film thickness tolerance, and light utilization efficiency, supported by mechanistic insights into aggregation and charge-generation dynamics. Furthermore, the approach is scaled to 100 cm² translucent module, which exhibits color quality and the practical potential of donor-diluted devices is validated through a 600 cm² power-generating window in a model house, thereby highlighting their relevance for BIPV applications. However, there are still some questions and issues that should be addressed.\n1. This manuscript lacks data on color rendering index and infrared rejection rate. Without this information, it is difficult to evaluate the semitransparent and thermal insulation performance quantitatively. Therefore, the authors should provide the following relevant data: color rendering index, infrared rejection spectra and geometrical fill factor.\n2. It is imperative to acknowledge the pivotal role of high carrier mobility in the fabrication of OSCs, particularly regarding their thickness tolerance. It is recommended that the authors provide data on the electron and hole mobility of single-component and blend films. This will demonstrate the materials’ potential for use in the production of module devices with thickness of approximately 300 nm.\n3. The manuscript contains some inaccuracies about the use and definition of certain abbreviations. For instance, the abbreviation “CCL” should be “crystalline coherence length” instead of “coherence length”. It is therefore recommended that authors undertake a systematic review of the entire manuscript to ensure that all abbreviations are accurately defined at first mention and used consistently throughout.\n4. The manuscript proposes that donor dilution lowers the viscosity of the BHJ solution, thereby accelerating the transition of the liquid film to a supersaturated state. However, the lack of viscosity measurements for BHJ solutions with varying donor content hinders the robustness of this mechanistic explanation. The authors should therefore provide corresponding viscosity data to support their claim.\n5. The photoluminescence quenching efficiency of the optimal D:A ratio of 1:3 PM6:Qx-p-4Cl should be given to better demonstrate enough exciton dissociation.\n6. The manuscript proposes that donor dilution reduces solution viscosity and thereby influences film formation dynamics. While low-viscosity solutions have been shown to enhance leveling, accelerated drying may induce Marangoni flows or abnormal phase separation, which could potentially compromise the continuity of the film. The suppression of Marangoni effects is widely recognized as a key factor in achieving favorable morphology. However, the absence of discussion on this aspect, as well as the lack of direct supporting evidence, weakens the mechanistic interpretation."}, "author_response": "A point-by-point response to the reviewers’ comments\nReviewer #1 (Remarks to the Author):\nThe authors realized excellent performance in large-area translucent devices with\nrobust film thickness tolerance, revealing the promising application prospects of ST-\nOSCs. It is of significant interest that the practicality of BIPVs for power generation,\nenergy storage, and temperature regulation has been confirmed through a scaled-down\nmodel featuring a 600 cm2 power-generating window. Besides, the unique aggregation\nmechanism and excited state dynamics in slot-die-coated donor-diluted blends were\nanalyzed, which can support their conclusions. The manuscript is well organized and\ndemonstrates the feasibility of ST-OSCs in BIPVs. I would like to recommend its\npublication in Nature Communications after minor revision.\n1. In Fig. 4c, the authors achieved high CTM in this work, however, the detailed\nLUE\nvalues are not mentioned in the manuscript nor listed in tables. The same issue is also\nobserved in Supplementary Fig. 34. The author should provide corresponding detailed\ndata. Additionally, please clarify the film thickness used for the CTM calculation\nLUE\nbetween the 1 cm2 device and the module.\nAuthor reply: We thank the reviewer for pointing out this issue. To address the\nreviewer’s concern, we have added the detailed CTM data in the manuscript and the\ncorresponding table. For the evaluation of CTM , the 100 cm2 ST-module achieves a\nLUE\nCTM value of 83% relative to a small-area (0.0256 cm2) ST-OSC. When compared\nLUE\nto a large-area (1 cm2) semitransparent device with 180 nm film thickness serving as\nthe reference, the ST-module exhibits a CTM of 85.13%. Regarding the calculation\nLUE\nof CTM of PCE (CTM ), the 100 cm2 ST-module shows a CTM of 84.07% relative\nPCE PCE\nto the small-area ST-OSC and 88.06% relative to the large-area ST-OSC (180 nm),\nrespectively. The related descriptions have been added in the highlighted text on pages\n13-14 of the revised Manuscript file and Supplementary Table 21 of the revised\nSupplementary file as follows:\n1\n On pages 13-14 in the revised Manuscript file:\n“Impressively, the 100 cm2 ST-module fabricated in our work yields a CTM of 83.00%\nLUE\nrelative to a small-area ST-device, which is nearly 1.5 times that of other reported 100\ncm2 ST-modules and is comparable to that of reported mini ST-modules (< 20 cm2).24\nWhen the large-area ST-device (180 nm) is taken as the reference, the ST-module shows\nCTM of 85.13%. Besides, similar results are also found in the summary of CTM of\nLUE\nPCE (CTM ). As shown in Supplementary Fig. 34 and Supplementary Table 20-21,\nPCE\nthe 100 cm2 ST-module shows a CTM of 84.07% relative to small-area ST-OSC and\nPCE\n88.06% relative to the large-area ST-OSC (180 nm), respectively. It is revealed that the\nhigh thickness tolerance improves the CTM of ST-module to a level comparable to\nPCE\nopaque modules (84%-88%) and significantly suppresses the performance loss during\nupscaling for ST-OSCs.”\n In the revised Supplementary file:\nSupplementary Table 21. The CTM of PCE and LUE of ST-OSCs, which is calculated\nfrom the equation of CTM = PCE /PCE and CTM = LUE\nPCE monolithic device module LUE monolithic\n/LUE , respectively.\ndevice module\nMonolithic device Module\nNu CTM CTM\nPCE LUE\nArea PCE LUE Area PCE LUE Ref.\nm. (%) (%)\n(cm2) (%) (%) (cm2) (%) (%)\n1 0.09 12.27 2.50 10.8 9.54 2.02 77.75 80.80\n2\n2 0.09 12.27 2.50 3.6 9.74 2.06 79.38 82.60\n3 0.04 8.30 1.90 12.8 7.5 1.67 90.36 87.89 5\n4 1.4 7.9 4.05 7.14 5.25 2.63 66.46 64.94 21\n5 - 12.6 3.9 21 10.2 3.3 80.95 84.62\n7\n6 - 12.6 3.9 100 6.7 2.2 53.17 56.41\n7 1.05 2.93 2.06 10.3 2.31 1.62 78.84 79.17\n12\n8 1.05 1.37 1.10 10.3 1.12 0.89 81.75 82.06\n9 0.063 13.31 6.02 16.8 11.3 4.53 84.90 75.25 22\n10 - 12.78 2.68 19.3 11.28 2.26 88.26 84.02 23\n11 0.04 12.07 5.04 120 6.69 2.70 55.43 53.57 24\n12 0.0256 12.37 4.00 100 10.40 3.32 84.07 83.00 This\nwork\n13 1 11.81 3.90 100 10.40 3.32 88.06 85.13\n2\n2. In Fig. 3c, why did stage 3 only appear in the donor-diluted slot-die-coated blends,\nwhile the slot-die-coated blend with 1:1 ratio shows the film-formation dynamic similar\nto the spin-coated blends? Interestingly, stage 3 is more pronounced in the blend with\nlower donor content, and the duration time of stage 3 becomes longer with diluting\ndonor content. Can authors give more explanations?\nAuthor reply: We thank the reviewer for pointing out this issue. During the slot-die\ncoating process, the solvent evaporation is accompanied by lateral solution diffusion,\nleading to continuous thinning of the liquid active layer. This behavior is significantly\ngoverned by viscosity. According to a previous report (Sci. China Mater. 2025, 68,\n2799), the low viscosity enhances the molecular diffusion of donor and acceptor species\nand reduces the solvent diffusion resistance, prolonging the diffusion duration, while\nthe diffusion in the blend with high viscosity is restricted. As shown in Supplementary\nTable 18, diluting donor content reduces the viscosity from 3.55 mPa s (1:1) to 1.33\nmPa s (1:5), thereby prolonging the duration of diffusion of the solution. This extended\ndiffusion process provides a mechanistic explanation for the emergence of stage 3\nexclusively in donor-diluted blends, not in the 1:1 blend. Furthermore, the lower\nviscosity enhances the prominence of stage 3 and prolongs its duration. The relevant\ndiscussions were highlighted on page 12 of the revised manuscript, and the related\nliterature (Sci. China Mater. 2025, 68, 2799) was cited as References 65 as follows:\n On page 12 in the revised Manuscript file:\n“It represents the further thinning of the active layer, followed by the formation of a\nsolid film. Notably, during slot-die coating, the solvent evaporation is accompanied by\nlateral solution diffusion across the substrate, which is fundamentally different from\nspin coating. This lateral spreading results in continuous thinning of the liquid film.\nThis behavior is significantly governed by viscosity. Low viscosity enhances the\nmolecular diffusion and reduces solvent diffusion resistance, thereby prolonging the\ndiffusion time. Conversely, high viscosity restricts diffusion dynamics.65 As shown in\nSupplementary Table 18, the PM6:Qx-p-4Cl solutions with 1:1, 1:3, and 1:5 exhibit\nviscosity of 3.55, 1.85, and 1.33 mPa s, respectively. The reduced viscosity prolongs\n3\nthe solution diffusion process, which directly accounts for the emergence and extended\nduration of stage 3 observed in donor-diluted slot-die-coated blends. Notably, the 1:5\nblend exhibits a longer stage 3 duration (0.7 s) compared to the 1:3 blend (0.4 s),\nattributed to its lower viscosity, which enhances lateral spreading and delays film\nsolidification. More importantly, the emergence of stage 3 in the 1:3 and 1:5 slot-die-\ncoated films demonstrates that acceptor aggregation occurs within the liquid film rather\nthan in a supersaturated state. As illustrated in Fig. 3d, this liquid-phase aggregation\nenables the formation of well-defined fibrillar structures and continuous percolating\nnetworks.”\n On page 24 in the References Section of the revised Manuscript file:\n65. Liu, C. et al. Solution viscosity-governed phase separation and aggregation kinetics\nenable high-efficiency, eco-friendly slot-die coated organic solar cells. Sci. China Mater.\n68, 2799-2808 (2025).\n3. For AFM measurement, the authors point out that the change of D:A ratio has a subtle\neffect on the fiber network structure of slot-die-coated blends via detecting the surface\nmorphology. Can D:A ratio affect the fiber size? The authors should provide some\ndiscussion on the microscopic scale.\nAuthor reply: We thank the reviewer for constructive comments on this work. To\nexplore the influence of the D:A ratio on fibril width, we performed a more in-depth\nanalysis of AFM data from the PM6:Qx-p-4Cl slot-die-coated blends with different D:A\nratios and quantified the fibril width via performing line profile analysis on AFM,\nas shown in Supplementary Fig. 19 of the revised Supplementary file. The films with\nratios of 1:1, 1:3, and 1:5 exhibit fibril widths of 20, 21, and 21 nm, respectively,\nindicating a negligible effect of donor dilution on the fibril width of slot-die-coated\nblends. This result is related to the special film-formation process in donor-diluted slot-\ndie-coated blend. The detailed discussions and data have been added with highlighted\ntext on page 7 of the revised Manuscript file and Supplementary Fig. 19 in the revised\nSupplementary file as follows:\n4\n On page 7 in the revised Manuscript file:\n“For slot-die-coated films, all the films with different D:A ratios exhibit consistent\nsurface morphology with lower R than spin-coated films. Notably, the obvious fibril-\nq\nlike structure with fibril width in the range of 20-21 nm can be observed even at an\nextreme D:A ratio (1:5), and diluting donor content has a negligible effect on fibril size\nas shown in Supplementary Fig. 19.”\n On pages 3 and 14 in the revised Supplementary file:\n“Supplementary Figure 19 | The fibril width of slot-die-coated PM6:Qx-p-4Cl blends\nwith different D:A ratios measured from AFM images.”\nSupplementary Figure 19. The AFM height images and statistics of fibril width of\nslot-die-coated PM6:Qx-p-4Cl films with D:A ratios of (a) 1:1, (b) 1:3 and (c) 1:5.\n5\n4. The change of D:A ratio can affect the absorption characteristics of bulk\nheterojunction blends; however, this work lacks absorption spectroscopy measurements\nof PM6:Qx-p-4Cl with different D:A ratios. The authors should include the relevant\nresults and provide further discussion.\nAuthor reply: Thanks very much for the reviewer’s suggestion. The absorption spectra\nof PM6:Qx-p-Cl with different D:A ratios (1:1, 1:3, and 1:5) were measured, as shown\nin Fig. 1b, to investigate the impact of donor dilution strategy on the absorption\ncharacteristics. The blend with lower donor content exhibits significantly reduced\nabsorption capacity in the visible range, indicating great potential of the donor dilution\nstrategy in realizing high AVT. The absorption spectra and relevant discussions were\nadded in Fig. 1b and pages 4-6 of the revised Manuscript file, respectively, as follows:\n On pages 4-6 in the revised Manuscript file:\n“The chemical structures of the PM6:Qx-p-4Cl system and thickness-normalized\nabsorption spectra of the blends with different D:A ratios are illustrated in Fig. 1a-b.”\n“As seen in Fig. 1b-d and Supplementary Fig. 11, diluting donor content within the\nactive layer significantly reduces the absorption in the visible range, realizing high AVT\nin donor-diluted ST-OSCs.”\nthickness-normalized absorption spectra of PM6:Qx-p-4Cl films. The device\nparameters statistics of (c) opaque and (d) semitransparent OSCs with different D:A\nratios. e The change of AVT against active layer thickness for spin-coated and slot-die-\ncoated PM6:Qx-p-4Cl blends (△d represents the thickness difference between 1:1.5 and\n1:3 blends at the same transmittance). f The J-V curves of slot-die-coated ST-devices\nwith MoO ARC, and the insert shows the corresponding device architecture. g The\n3\ntransmittance spectra of small-area and large-area ST-devices. h The summary of LUE\nversus active layer thickness of reported large-area ST-OSCs (≥ 1 cm2).\n5. Some minor mistakes should be proofed throughout the article: (1) The black data\npoints in Fig. 1e are of different sizes; (2) The detailed temperature data in Fig. 4h\nshould be listed in a table.\nAuthor reply: We thank the reviewer for the thoughtful review of the manuscript. We\nhave modified Fig. 1e in the original manuscript and summarized the temperature data\n7\nin Supplementary Table 22. The description of Supplementary Table 22 was added in\nhighlighted text on page 14 of the revised manuscript. The corresponding corrections\nhave been added in Fig. 1h in the revised Manuscript file and Supplementary Table 22\nin the revised Supplementary file as follows:\n In the revised Manuscript file:\nFig. 1|Device characteristics. a Chemical structures of PM6 and Qx-p-4Cl. b. The\nthickness-normalized absorption spectra of PM6:Qx-p-4Cl films. The device\nparameters statistics of (c) opaque and (d) semitransparent OSCs with different D:A\nratios. e The change of AVT against active layer thickness for spin-coated and slot-die-\ncoated PM6:Qx-p-4Cl blends (△d represents the thickness difference between 1:1.5 and\n1:3 blends at the same transmittance). f The J-V curves of slot-die-coated ST-devices\nwith MoO ARC, and the insert shows the corresponding device architecture. g The\n3\ntransmittance spectra of small-area and large-area ST-devices. h The summary of LUE\nversus active layer thickness of reported large-area ST-OSCs (≥ 1 cm2).\n8\n On page 14 in the revised Manuscript file:\n“The detailed temperature data are listed in Supplementary Table 22.”\n On pages 4 and 32 in the revised Supplementary file:\n“Supplementary Table 22 | The summary of temperature inside the house model.”\nSupplementary Table 22. The summary of the temperature inside the house model at\ndifferent irradiation time.\nIrradiation time (min) Temperature (℃)\n0 21.3\n3 21.6\n6 21.8\n9 22.3\n12 22.9\n15 23.5\n18 24.1\n21 24.9\n24 25.5\n27 25.9\n30 26.2\n33 26.5\n36 28.1\n39 29.1\n42 30.5\n45 31.6\n48 32.6\n51 33.3\n54 34.0\n57 34.6\n60 35.2\n63 35.7\nReviewer #2 (Remarks to the Author):\nIn the manuscript, the authors have developed a new system, fabricated via slot-die\ncoating with a non-halogen solvent in ambient air, that can maintain high light\nutilization efficiency (LUE) while showing exceptional film thickness tolerance from\n100 to 300 nm. This development represents a substantial advancement for semi-\ntransparent organic solar cells (ST-OSCs), which traditionally achieve high LUE at film\nthicknesses of less than 100 nm. Additionally, the authors utilized a scaled-down house\nmodel featuring a 600 cm² power-generating window to demonstrate the potential of\nBIPVs for power generation, energy storage, and temperature regulation, highlighting\nthe promise of donor-diluted translucent devices for real-world applications. I suggest\nthat the manuscript be accepted with minor revisions.\n1. Fig. 2 demonstrated both the mechanism behind the high-performance donor-diluted\nST-OSCs and the generality of the donor-dilution strategy by employing a combination\nof TA technology, L calculation, and multi-photovoltaic system comparative studies.\nD\nIn fact, there are some minor logical confusions here. Firstly, the excited state behaviors\nare closely related to morphology; however, this work discusses less about the influence\nof morphology on excited state dynamics. Secondly, the discussions in this section\nwould benefit from phase domain size analysis, as the domain size and L collectively\nD\naffect whether exciton can reach the donor-acceptor interface. Additionally, in my\nopinion, the inclusion of the analysis of E here seems tangential to the main focus issue.\nb\nTherefore, the authors need to reorganize the discussions in this section to improve the\noverall logic.\nAuthor reply: Thanks very much for the reviewer’s suggestion. We correlated the\nresults of excited state dynamics with morphology analysis and presented an in-depth\ndiscussion. For spin-coated blends, diluting the donor content leads to greater acceptor-\nphase aggregation, fewer donor/acceptor interfaces, and disruption of the fiber network\nstructure. Therefore, the transient absorption measurement exhibits that the charge\ntransfer, LE dynamics, and charge transport are impeded with gradually diluting donor\ncontent, as shown in Fig. 2f, Supplementary Fig. 18, and Supplementary Table 11-13.\nOn the contrary, the slot-die-coated films with different D:A ratios exhibit more ideal\nmorphology compared to spin-coated films and a prominent fiber network structure,\nwhich enables efficient charge transfer and transport, as shown in Fig. 2g. To provide\nquantitative analysis, the fibril widths and L are quantified as shown in Supplementary\nD\nsimilar method as the relevant studies (Nat. Commun., 2024, 15, 6865; Nat. Mater.,\n2022, 21, 656; Small, 2025, 21, 2411698; Energy Environ. Sci., 2023, 16, 1062; Adv.\nMater., 2023, 35, 2208211; Adv. Energy Mater., 2024, 2404062.). These literatures are\ncited as 50-55 in the References Section of the revised manuscript. PM6:Qx-p-4Cl\nmaintains a similar morphology and fibril width (~ 21 nm) across different D:A ratios.\nTherefore, the LD of Qx-p-4Cl (22.34 nm) is sufficient to ensure efficient exciton\ndynamics even in donor-diluted films, as evidenced by TRPL (Supplementary Fig. 27).\nFurthermore, the fibril widths of PM6:Y6 films with different D:A ratios are nearly\nidentical (~ 24 nm), leading to similar exciton dynamics (Supplementary Fig. 28-29 and\nSupplementary Table 16). In contrast, for L8-BO- and Qx-1-based systems, an increase\nin fibril width is observed with donor dilution. It is indicated that fewer D/A interfaces\nin donor-diluted blends increase the exciton lifetime. The corresponding discussions\nare added in the highlighted text on pages 8-10 of the revised Manuscript file.\nAccording to the reviewer’s comments, we have shifted the focus of this section to\nthe L and the fibril width and reorganized the logic of this section. Firstly, we have\nD\nrelocated the discussions on the device performance based on PM6:Y6, PM6:L8-BO,\nand PM6:Qx-1 to the section of Photovoltaic properties (the highlighted text on page 4\nof the revised Manuscript file) and provided a more comprehensive analysis. Secondly,\nthe sections of Abstract and Discussion have been refined to maintain the logical\ncoherence of the manuscript due to the change in logic. Next, we slightly modified Fig.\n2 in the revised Manuscript file to enhance reader comprehension. Meanwhile, we have\nremoved the summary of R values in Supplementary Fig. 22 of the original\nq\nSupplementary file, because the relevant data have already been provided in\nSupplementary Table 10.\nThe corresponding modifications are shown as follows:\n On pages 8-10 in the revised Manuscript file:\n“Fig. 2f shows the kinetic decay curves for spin-coated films, revealing that increasing\nthe acceptor content suppresses the hole transfer process, as evidenced by a progressive\n11\nlengthening of the rise time of the PM6 GSB signal. As summarized in Supplementary\nTable 11, the half-time of rise (t ) for the GSB signal increases from 0.39 ps in the\nhalf-time\n1:0.5 blend to 0.50 ps in the 1:1.5 blend and further to 0.61 ps in the 1:3 blend. The\nearly-stage lifetime of the LEs kinetic trace is also extracted to assess the dissociation\nof excitons, as shown in Supplementary Table 12, and the fitted lifetime grows from\n0.29 in the 1:0.5 blend to 0.58 ps in the 1:3 blend. This prolonged LE lifetime implies\nthat excitons remain localized for a longer duration before dissociating. Besides, the\nincreased acceptor content in the spin-coated blend can accelerate the charge decay as\nthe polaron signal of the blend with higher acceptor content shows more rapid decay\n(Fig. 2f and Supplementary Table 13).49 For slot-die-coated films, Fig. 2g demonstrates\nthat highly efficient charge generation is achieved across all D:A ratios. The\ncorresponding t values fall within a narrow range of 0.27-0.36 ps, which is\nhalf-time\ncomparable to that of the non-diluted films fabricated with spin coating. Similarly, the\npolaron signal dynamics show consistent behavior across different ratios, further\nconfirming the robustness of charge generation and transport in slot-die-coated films.\nThe underlying mechanism for these divergent behaviors is elucidated through AFM\nanalysis. For spin-coated films, the extreme D:A ratio in donor-diluted film results in\nlarge phase aggregation of acceptor (Fig. 2c), leading to insufficient donor/acceptor\ninterface, which severely hampers exciton dissociation and charge transfer. Meanwhile,\nthe loss of the interconnected network is responsible for the limitation in charge\ntransport for donor-diluted films. In contrast, the more ideal morphology with\nprominent fibrous features in slot-die-coated films with different D:A ratios ensures an\nefficient and nearly identical charge transfer process and charge transport, indicating\nthat the donor dilution strategy has a negligible effect on excited state dynamics in\nPM6:Qx-p-4Cl slot-die-coated films.\nAs shown in Supplementary Fig. 19-22, and Supplementary Fig. 26, we quantified the\nexciton diffusion length (L ) and fibril width of slot-die-coated films to verify the above\nD\nconclusions.50-55 The calculated L values are listed in Supplementary Table 14-15.56-59\nD\nIt is evident that the fibril widths in all the slot-die-coated PM6:Qx-p-4Cl films are\n12\nsimilar (~ 21 nm), and the larger L of Qx-p-4Cl (22.34 nm) enables efficient exciton\nD\ndissociation, as confirmed by a photoluminescence quenching efficiency (PLQE) above\n90% (Supplementary Fig. 27). The fibril widths of PM6:Y6 films with different D:A\nratios are nearly identical (~ 24 nm), leading to similar exciton dynamics as shown in\ntime-resolved photoluminescence (TRPL) measurement (Supplementary Fig. 25,\nSupplementary Fig. 28-29, and Supplementary Table 16). In contrast, for L8-BO- and\nQx-1-based systems, a slight increase in fibril width is observed with donor dilution,\nindicating reduced D/A interface and suppressed exciton dissociation in donor-diluted\nblends. These results are consistent with performance characteristics.”\n On page 4 in the revised Manuscript file:\n“Besides, we summarized the photovoltaic parameters of PM6:Y6, PM6:L8-BO,\nand PM6:Qx-1 with different D:A ratios in Supplementary Fig. 2-9 and Supplementary\nTable 3-5. All the slot-die-coated systems show high performance at a high acceptor\nratio. In particular, the PM6:Y6 devices achieve the optimal efficiency when the\nacceptor ratio exceeds twice that of the donor. However, the best performance of\nPM6:L8-BO and PM6:Qx-1 devices is obtained at D:A ratios of 1:1.7 and 1:1.5,\nrespectively. Further dilution of donor content leads to a decline in device performance.”\nPM6:Qx-p-4Cl donor-diluted films processed by spin coating and slot-die coating. b\nThe summary of CCL values. c AFM height images of donor-diluted spin-coated and\nslot-die-coated films. TA maps for (d) spin-coated film (1:1.5) and (e) slot-die-coated\nfilm (1:3). The hole transfer, LE dynamics, and polaron kinetics of (f) spin-coated and\n(g) slot-die-coated films with different D:A ratios.\n Abstract Section on page 1 in the revised Manuscript file:\n“Using PM6:Qx-p-4Cl as a model system, we elucidate a unique film-formation\nmechanism and charge generation process, demonstrating that the fiber network and\nsuitable aggregation size are crucial for ensuring higher performance in donor-diluted\nST-OSCs.”\n Discussion Section on page 16 in the revised Manuscript file:\n“Meanwhile, the exciton diffusion length is longer than the aggregation size, ensuring\nthe efficient charge generation in donor-diluted blends.”\n On page 23 in References Section of the revised Manuscript file:\n14\n50. Chen, C. et al. Molecular interaction induced dual fibrils towards organic solar cells\nwith certified efficiency over 20%. Nat. Commun. 15, 6865 (2024).\n51. Zhu, L. et al. Single-junction organic solar cells with over 19% efficiency enabled\nby a refined double-fibril network morphology. Nat. Mater. 21, 656-663 (2022).\n52. Wang, Y. et al. High-performance g-dimer acceptor-based flexible organic solar\ncells optimized by temperature-dependent film formation process. Small 21, e2411698\n(2025).\n53. Chen, H. et al. A 19% efficient and stable organic photovoltaic device enabled by a\nguest nonfullerene acceptor with fibril-like morphology. Energy Environ. Sci. 16, 1062-\n1070 (2023).\n54. Li, D. et al. Fibrillization of non-fullerene acceptors enables 19% efficiency pseudo-\nbulk heterojunction organic solar cells. Adv. Mater. 35, e2208211 (2023).\n55. Feng, W. et al. Rational design of two well‐compatible dimeric acceptors through\nregulating chalcogen‐substituted conjugated backbone enable ternary organic solar\ncells with 19.4% efficiency. Adv. Energy Mater. 2404062 (2024).\n On pages 3 and 14-16 in the revised Supplementary file:\n“Supplementary Figure 19 | The fibril width of slot-die-coated PM6:Qx-p-4Cl blends\nwith different D:A ratios measured from AFM images.\nSupplementary Figure 20 | The fibril width of slot-die-coated PM6: Y6 blends with\ndifferent D:A ratios measured from AFM images.\nSupplementary Figure 21 | The fibril width of slot-die-coated PM6:L8-BO blends with\ndifferent D:A ratios measured from AFM images.\nSupplementary Figure 22 | The fibril width of slot-die-coated PM6:Qx-1 blends with\ndifferent D:A ratios measured from AFM images.”\nslot-die-coated PM6:Qx-p-4Cl films with D:A ratios of (a) 1:1, (b) 1:3 and (c) 1:5.\nslot-die-coated PM6:Y6 films with different D:A ratios.\nslot-die-coated PM6:L8-BO films with different D:A ratios.\nslot-die-coated PM6:Qx-1 films with different D:A ratios.\n2. There is insufficient discussion of TA spectroscopy in this article, especially for the\nhole transfer process. More discussions are needed. Importantly, this manuscript would\nbe strengthened by including a comparison of the dynamics between spin-coated and\nslot-die-coated blends. In addition, the information on probe wavelength and pump\nwavelength is missing in Fig. 2f-g, which will confuse readers. The authors need to\ncomplete the relevant information.\nAuthor reply: We thank the reviewer for pointing out this issue. Following the\nreviewer’s comments, we have expanded the discussions on the transient absorption\ncharacteristics and compared the excited state dynamics between spin-coated and slot-\ndie-coated films. As shown in Fig. 2f, the spin-coated films with different D:A ratios\nexhibit a significant difference. The values of half-time of rising of PM6 GSB signal\n(t ), which represents the kinetics of hole transfer, of 1:0.5. 1:1.5 and 1:3 D:A\nhalf-time\nratios are 0.39, 0.50, and 0.61 ps, respectively. The consistent results are also observed\nin the measurement of excitation states (LEs), as shown in Supplementary Table 12. In\naddition, the dilution of donor content accelerates the charge decay as the polaron signal\n18\nof the spin-coated blend with higher acceptor content shows more rapid decay\n(Fig. 2f and Supplementary Table 13). In contrast, the nearly identical charge transfer processes\nand LE dynamics are observed in slot-die-coated films with different D:A ratios due to\nthe more ideal morphology than donor-diluted spin-coated films (Fig. 2g). The\ncorresponding t values fall within a narrow range of 0.27-0.36 ps, which is\nhalf-time\ncomparable to that of the non-diluted films fabricated with spin coating. Meanwhile,\nthe prominent fibrous feature ensures similar decay curves of the polaron signal in all\nthe slot-die-coated films. For clarity, the information on probe wavelength and pump\nwavelength has been included in Fig. 2f-g, and the LE dynamics curves in the original\nSupplementary file are shifted to Fig. 2 in the revised manuscript. Meanwhile, we\nremoved Fig. 2h in the original manuscript because the L data have already been listed\nD\nin Supplementary Table 15, and Fig. 2i in the original manuscript is shifted to\nSupplementary Fig. 25 in the revised Supplementary file. The related discussions and\nrevised Fig. 2 can be found on pages 8-10 of the revised Manuscript file as follows:\n On pages 8-10 in the revised Manuscript file:\n“Fig. 2f shows the kinetic decay curves for spin-coated films, revealing that increasing\nthe acceptor content suppresses the hole transfer process, as evidenced by a progressive\nlengthening of the rise time of the PM6 GSB signal. As summarized in Supplementary\nTable 11, the half-time of rise (t ) for the GSB signal increases from 0.39 ps in the\nhalf-time\n1:0.5 blend to 0.50 ps in the 1:1.5 blend and further to 0.61 ps in the 1:3 blend. The\nearly-stage lifetime of the LEs kinetic trace is also extracted to assess the dissociation\nof excitons, as shown in Supplementary Table 12, and the fitted lifetime grows from\n0.29 in the 1:0.5 blend to 0.58 ps in the 1:3 blend. This prolonged LE lifetime implies\nthat excitons remain localized for a longer duration before dissociating. Besides, the\nincreased acceptor content in the spin-coated blend can accelerate the charge decay as\nthe polaron signal of the blend with higher acceptor content shows more rapid decay\n(Fig. 2f and Supplementary Table 13).49 For slot-die-coated films, Fig. 2g demonstrates\nthat highly efficient charge generation is achieved across all D:A ratios. The\ncorresponding t values fall within a narrow range of 0.27-0.36 ps, which is\nhalf-time\n19\ncomparable to that of the non-diluted films fabricated with spin coating. Similarly, the\npolaron signal dynamics show consistent behavior across different ratios, further\nconfirming the robustness of charge generation and transport in slot-die-coated films.\nThe underlying mechanism for these divergent behaviors is elucidated through AFM\nanalysis. For spin-coated films, the extreme D:A ratio in donor-diluted film results in\nlarge phase aggregation of acceptor (Fig. 2c), leading to insufficient donor/acceptor\ninterface, which severely hampers exciton dissociation and charge transfer. Meanwhile,\nthe loss of the interconnected network is responsible for the limitation in charge\ntransport for donor-diluted films. In contrast, the more ideal morphology with\nprominent fibrous features in slot-die-coated films with different D:A ratios ensures an\nefficient and nearly identical charge transfer process and charge transport, indicating\nthat the donor dilution strategy has a negligible effect on excited state dynamics in\nPM6:Qx-p-4Cl slot-die-coated films.”\nFig. 2|Morphology and photophysics characteristics. a The 2D GIWAXS patterns of\nPM6:Qx-p-4Cl donor-diluted films processed by spin coating and slot-die coating. b\nThe summary of CCL values. c AFM height images of donor-diluted spin-coated and\nslot-die-coated films. TA maps for (d) spin-coated film (1:1.5) and (e) slot-die-coated\n20\nfilm (1:3). The hole transfer, LE dynamics, and polaron kinetics of (f) spin-coated and\n(g) slot-die-coated films with different D:A ratios.\n On pages 3 and 17 in the revised Supplementary file:\n“Supplementary Figure 25 | The summary of exciton lifetimes.”\nSupplementary Figure 25. The summary of exciton lifetimes normalized against 1:0.5\nfilms.\n3. In the measurement of in-situ UV-Vis spectra, the authors proposed that the solution\nremoval during film formation results in a drop in absorption intensity. However, the\nproposed explanation is inconsistent with the splashing-free nature of slot-die coating\nmethod, which distinctly differentiates it from spin coating. This manuscript should\ndiscuss alternative reasons for the absorption decrease in slot-die coating.\nAuthor reply: We thank the reviewer for pointing out this issue. In Fig. 3d, we have\nconsidered only solvent evaporation during the film-formation process, while\nneglecting other possible solvent behaviors. In fact, the solvent removal mechanism\nduring the film-formation process in slot-die coating is distinct from that in spin coating.\nIt is worth noting that the solvent evaporation is accompanied by lateral solution\ndiffusion during slot-die coating, resulting in continuous thinning of the liquid active\nlayer. This behavior is significantly governed by viscosity. Low viscosity enhances the\nmolecular diffusion and reduces solvent diffusion resistance, thereby prolonging the\ndiffusion time. Conversely, high viscosity restricts diffusion dynamics. In this work,\n21\ndiluting donor content reduces the viscosity, as shown in Supplementary Table 18,\nthereby promoting the emergence of stage 3 in donor-diluted blends. According above\nresults, we have revised the film-formation mechanism in Fig. 3d. The relevant\ndiscussions were added in highlight text on page 12 of the revised manuscript, and Fig.\n3d was also revised as follows:\n On page 12 in the revised Manuscript file:\n“It represents the further thinning of the active layer, followed by the formation of a\nsolid film. Notably, during slot-die coating, the solvent evaporation is accompanied by\nlateral solution diffusion across the substrate, which is fundamentally different from\nspin coating. This lateral spreading results in continuous thinning of the liquid film.\nThis behavior is significantly governed by viscosity. Low viscosity enhances the\nmolecular diffusion and reduces solvent diffusion resistance, thereby prolonging the\ndiffusion time. Conversely, high viscosity restricts diffusion dynamics.65 As shown in\nSupplementary Table 18, the PM6:Qx-p-4Cl solutions with 1:1, 1:3, and 1:5 exhibit\nviscosity of 3.55, 1.85, and 1.33 mPa s, respectively. The reduced viscosity prolongs\n22\nthe solution diffusion process, which directly accounts for the emergence and extended\nduration of stage 3 observed in donor-diluted slot-die-coated blends. Notably, the 1:5\nblend exhibits a longer stage 3 duration (0.7 s) compared to the 1:3 blend (0.4 s),\nattributed to its lower viscosity, which enhances lateral spreading and delays film\nsolidification. More importantly, the emergence of stage 3 in the 1:3 and 1:5 slot-die-\ncoated films demonstrates that acceptor aggregation occurs within the liquid film rather\nthan in a supersaturated state. As illustrated in Fig. 3d, this liquid-phase aggregation\nenables the formation of well-defined fibrillar structures and continuous percolating\nnetworks.”\n On page 11 in the revised Manuscript:\nFig. 3|Film formation process analysis. a Time evolution maps of absorption spectra\ncontour maps. Time evolution of peak location and intensity of Qx-p-4Cl in (b) spin-\ncoated films and (c) slot-die-coated films. d The schematic illustration of the film-\nformation process of spin-coated and slot-die-coated films.\n4. The EQE, transmittance (T) and reflectance (R) spectra are necessary for the study\nof ST-OSCs. This article measured the EQE and transmittance spectra, but lacked the\ncharacteristics of the reflectance spectrum. The authors need to add the reflectance\nspectrum and the EQE+T+R spectrum in this article to support the results of device\nperformance.\nAuthor reply: We thank the reviewer for the constructive comment. In order to enhance\nthe comprehensiveness of the data presented in this study, we measured the reflectance\nand EQE+T+R spectra of three representative ST-OSCs, including a small-area\nsemitransparent device, large-area semitransparent devices with thicknesses of 119\n23\nand 180 nm. The corresponding results have been provided in Supplementary Fig. 12, and\nthe transmittance spectra of large-area ST-OSCs with other thicknesses (195, 206, 260,\nand 301 nm) were transferred from Supplementary Fig. 12 of the original\nSupplementary file to Supplementary Fig. 10 of the revised Supplementary file. The\nrelated discussions and revised figures have been shown in highlighted text on page 5\nof the revised manuscript and revised Supplementary file as follows:\n On page 5 in the revised Manuscript file:\n“The corresponding EQE spectra are shown in Supplementary Fig. 10. The slot-die-\ncoated ST-device with a small active layer area (0.0256 cm2) yields a V of 0.87 V, J\nOC SC\nof 19.85 mA cm-2, FF of 71.66% and PCE of 12.37%. For large-area ST-OSCs with\ndifferent thicknesses, the 1 cm2 device with 180 nm active layer shows the highest PCE\nof 11.81%, along with a V of 0.89 V, J of 18.86 mA cm-2, and FF of 70.32%. When\nOC SC\nthe active layer thickness is increased to 301 nm, the PCE is slightly reduced to 11.25%.\nIt is worth noting that the introduction of ARC improves the AVT of thick-film ST-\ndevices to more than 30% (Fig. 1f and Supplementary Fig. 10-12), indicating\noutstanding optical behaviors as shown in Supplementary Fig. 14.”\n On pages 2 and 9-10 in the revised Supplementary file:\n“Supplementary Figure 10 | EQE and transmittance spectra of 1 cm2 slot-die-coated\nsemitransparent PM6:Qx-p-4Cl devices.”\n“Supplementary Figure 12 | The EQE, reflection, and transmittance spectra of PM6:Qx-\np-4Cl 1 cm2 slot-die-coated semitransparent devices with ARC.”\nsemitransparent devices with different D:A ratios, (b) MoO -modified PM6:Qx-p-4Cl\n3\n(1:3) semitransparent devices with different device area, and (c) larger active layer\nthickness. (d) The transmittance spectra of the MoO ARC-modified large-area\n3\nsemitransparent device with different active layer thicknesses.\nSupplementary Figure 12. The EQE, transmittance (T), reflection spectra (R), and\nEQE+T+R of MoO ARC-modified (a) small-area semitransparent device, (b) 119 nm,\n3\nand (c) 180 nm large-area semitransparent device.\n5) The calculation method of GFF is missing. The authors need to add the information\nin the methods section.\nfactor (GFF) is defined as the ratio of the effective area of the module to the total module\narea, and a detailed calculation method of the GFF parameter has been added in the\nhighlighted text on page 19 in the Methods Section of the revised manuscript as follows:\n On page 19 in the Methods Section of the revised Manuscript file:\n“The geometric fill factor (GFF) is defined as the ratio of the effective area of the\nmodule (A ) (i.e., the total active layer area of all the sub-cells) to the total\neffective area\nmodule area (A ):\nmodule area\nGFF = A n×l×W W\neffective area\n= = (3)\nA n×l×(W+w) W+w\nmodule area\nwhere n and l represent the number of sub-cells and the length of sub-cells, respectively.\nThe W is the width of the sub-cell, and the w is the width of the dead area (i.e., the\ndistance between P1 and P3).”\n6) Closely related papers should be cited, such as Nat Commun 2025, 16, 7421; Adv.\nMater. 2025, 37, 2420439; Adv. Funct. Mater. 2023, 33, 2212601.\nAuthor reply: We thank the reviewer for pointing out this issue. The literature\nrecommended has been incorporated in paragraphs 1-2 of the Introduction Section, and\ncited as References 5, 6, and 14, respectively. Besides, a recent study in Joule (Joule\n2025, 9, 102173) reports impressive parameters in 120 cm2 ST-modules (PCE = 6.69%,\nAVT = 40.3%, LUE = 2.79%, CTM = 55.36%), offering detailed insights into the\nLUE\nfabrication of ST-modules. To comprehensively illustrate the current progress of ST-\nmodules, we have incorporated the device performance data into the statistical figure\nand table in our work (Fig. 4c, Supplementary Fig. 34, and Supplementary Table 21).\nThis study is cited as Reference 69 in the revised Manuscript file and Reference 24 in\nthe revised Supplementary file. The references in this part were reordered to improve\nthe coherence. The related modifications were highlighted on pages 2, 13, 15, 19, 20\nand 24 of the revised manuscript and pages 21, 32, and 36 in the revised Supplementary\nfile as follows:\n26\n On pages 19, 20, and 24 in the References Section of the revised Manuscript\nfile:\n5. Wang, D. et al. High-performance and eco-friendly semitransparent organic solar\ncells for greenhouse applications. Joule 5, 945-957 (2021).\n6. Yu, J. et al. Semitransparent organic photovoltaics with wide geographical\nadaptability as sustainable smart windows. Nat. Commun. 16, 7421 (2025).\n14. Xie, D. et al. A 2.20 eV bandgap polymer donor for efficient colorful smitransparent\norganic solar cells. Adv. Funct. Mater. 33, 2212601 (2023).\n69. Xie, D. et al. Scalable polymer for large-area semitransparent organic photovoltaics.\nJoule 9, 102173 (2025).\n On page 35 in the revised Supplementary file:\n24. Xie, D. et al. Scalable polymer for large-area semitransparent organic photovoltaics.\nJoule 9, 102173 (2025).\nReviewer #3 (Remarks to the Author):\nIn their manuscript “Scalable Semitransparent Organic Solar Cells with Robust Film\nThickness Tolerance for Building-Integrated Photovoltaics”, the authors present slot-\ndie coated semitransparent organic solar cells and modules with high LUE. I find the\ntopic relevant, but I think the following questions need to be addressed before the\nmanuscript can be accepted in Nature Communications:\n• The authors speak of translucent cells and modules. Is this used with the same meaning\nas semitransparent, or is there a difference?\nAuthor reply: Thanks very much for the reviewer’s suggestion. In this work, the terms\nof “translucent” and “semitransparent” are used to express the same meaning. However,\nthe presence of two different expressions can confuse readers. Therefore, we adopted a\nunified expression to ensure consistency, the term “translucent” has been replaced with\n“semitransparent”. In particular, the high-frequency phrases, “translucent device” and\n“translucent module”, have been revised to “semitransparent device (ST-device)” and\n“semitransparent module (ST-module)”, respectively. Throughout the Manuscript file\n27\nand Supplementary file, the term “translucent” appeared 23 times in the Manuscript file\nand 18 times in the Supplementary file. These modifications have been highlighted on\npages 1-6, 12-16, and 25 of the revised Manuscript file and pages 2-4, 9-11, 27-28, and\n31 of the revised Supplementary file.\n• I do not completely understand the cell-to-module efficiency remaining ratio (CTM)\nthat the authors introduce. Do they compare the efficiency of the semitransparent\nmodule the to the opaque cell? That would not be a fair comparison. If they compare\nthe semitransparent cell with the semitransparent module, I do not understand why the\nvalues is so low.\nAuthor reply: Thanks very much for the reviewer’s suggestion. The parameter of CTM\nis introduced not to compare the semitransparent module with an opaque cell, but rather\nto evaluate the performance difference between a device and its module of the same\ntype. For instance, the statistics of CTM in Fig. 4c of the manuscript and Supplementary\nTable 21 of the supplementary file show the ratio of performance (PCE and LUE)\nbetween the monolithic semitransparent device and the corresponding semitransparent\nmodule. Furthermore, for reference, the CTM values of the opaque module to\nPCE\nopaque cell are summarized in Supplementary Table 20.\nSecondly, the semitransparent modules with an area above 100 cm2 reported in\nprevious works show CTM lower than 54%, which is attributed to two main sources:\n(1) the design of the module and (2) scaling up production of the active layer. For the\ndesign of module structure, the presence of dead area and electrical contact resistance\nof the interconnects between subcells results in electrical loss and geometric loss,\ndegrading the PCE in modules. Besides, the traditional small-area ST-OSCs maintain\nthe high LUE threshold at approximately 60-80 nm active layer thickness, which is\nsignificantly thinner than that of high-performance opaque small-area devices (100-150\nnm). The large active layer thickness is necessary to meet the requirements of large-\nscale manufacturing, but results in a reduction in transmittance and device performance.\nConsequently, the CTM of a semitransparent module is very low and typically lower\n28\nthan that of an opaque module (~88%).\nTo achieve a high-performance semitransparent module, we adopted the donor\ndilution strategy to improve the PCE and AVT of thick-film ST-OSCs in this work. The\n100 cm2 donor-diluted semitransparent module based on PM6:Qx-p-4Cl yields CTM\nabove 80%, which is comparable to that of the reported opaque module. The related\ndiscussions were added in highlighted text on page 3 of the revised manuscript as\nfollows:\n On page 3 in the revised Manuscript file:\n“Impressively, the CTM of ST-OSCs is generally lower than that of opaque OSCs.\nEspecially for the ST-module with an area above 100 cm2, the reported CTM of the 100\ncm2 ST-module is around 56%, which lags far behind the 100 cm2 opaque module\nreported in previous works (~ 88%).23, 24 In addition to inherent electric and geometric\nlosses of the module design, this performance gap primarily stems from the increased\nactive layer thickness during scaling up production, which reflects the fundamental\nchallenge of fabricating very thin film using scalable fabrication technologies. However,\nthe large active layer thickness leads to enhanced recombination, poor charge extraction,\nand reduced transmittance, resulting in exacerbated degradation of LUE for ST-OSCs.25,\nimprove the film thickness tolerance for preparing high-performance upscaling ST-\nmodules.27”\n• How general is the difference between spin-coating and slot-die coating that is shown\nin Figure 1b? The authors have investigate the morphology and photophysics for\ndifferent blends, have they also analyzed the device performance?\nAuthor reply: We thank the reviewer for pointing out this issue. To comprehensively\nanalyze the performance differences between spin-coated and slot-die-coated devices,\nwe have supplemented the discussion of device performance for PM6:Y6, PM6:L8-BO,\nand PM6:Qx-1 in the photovoltaic properties section. As shown in Supplementary Fig.\n2-9 and Supplementary Table 3-5, all the slot-die-coated systems exhibit high\n29\nperformance at high acceptor ratios. Especially for PM6:Y6, the peak efficiency of the\nslot-die-coated PM6:Y6 device is achieved when the acceptor ratio exceeds twice the\ndonor. And the optimal D:A ratio for PM6:L8-BO and PM6:Qx-1 systems are 1:1.7 and\n1:1.5, respectively. Morphology and TRPL measurements can well explain these results.\nAs shown in Fig. 2 and Supplementary Figure 19-22, the fibril widths of slot-die-coated\nPM6:Qx-p-4Cl with different D:A ratios are similar, enabling efficient exciton\ndissociation and high performance in a donor-diluted device. This trend extends to the\nPM6:Y6 system. While a slight increase in fibril width with donor dilution is observed\nin L8-BO and Qx-1 systems, this results in longer exciton lifetimes and lower efficiency\nin donor-diluted blends. These results are consistent with the performance\ncharacteristics and demonstrate the crucial effect of morphology on charge generation\nin donor-diluted blends. The relevant discussions were added in highlighted text on\npage 4 of the revised manuscript as follows:\n On page 4 in the revised Manuscript file:\n“Besides, we summarized the photovoltaic parameters of PM6:Y6, PM6:L8-BO,\nand PM6:Qx-1 with different D:A ratios in Supplementary Fig. 2-9 and Supplementary\nTable 3-5. All the slot-die-coated systems show high performance at a high acceptor\nratio. In particular, the PM6:Y6 devices achieve the optimal efficiency when the\nacceptor ratio exceeds twice that of the donor. However, the best performance of\nPM6:L8-BO and PM6:Qx-1 devices is obtained at D:A ratios of 1:1.7 and 1:1.5,\nrespectively. Further dilution of donor content leads to a decline in device performance.”\n• On page 3, the authors write that thin active layers face exacerbated performance\ndegradation when up-scaled. Can they clarify what they mean by performance\ndegradation, and give a reference for that?\nAuthor reply: We thank the reviewer for the constructive comment. In general,\nhigh-performance OSCs realize the optimal PCE at a thin active layer (100-150 nm)\nvia spin coating technology. Especially for ST-OSCs, an ultrathin active layer (< 80 nm)\nis\nemployed to balance the efficiency and transparency. However, the thin film can not\n30\nmeet the requirement of scaling up production according to previous reports (Adv.\nMater. 2019, 31, 1805089 and Nat. Mater., 2025, 24, 444). Firstly, it is difficult to\nfabricate thin films by most scalable fabrication technologies. Secondly, achieving a\nuniform film is challenging for large-area fabrication due to process instability.\nTherefore, a large number of point defects will exist in large-area OSCs, resulting in\nsignificant charge loss because the thin film is sensitive to the defects. Importantly,\nlarger active layer thickness leads to increased recombination, reduced charge\nextraction, and thus exacerbated efficiency degradation, especially for the photovoltaic\nsystems with weak thickness tolerability. Consequently, it is necessary to realize high\nAVT and PCE for ST-OSCs with a thick-film active layer for preparing a high-\nperformance, large-area semitransparent module. The relevant discussions were added\nin highlighted text on page 3 of the revised manuscript, and the supporting literatures\n(Adv. Mater. 2019, 31, 1805089 and Nat. Mater., 2025, 24, 444) were cited as\nReferences 25 and 26 as follows:\n On page 3 in the revised Manuscript file:\n“Impressively, the CTM of ST-OSCs is generally lower than that of opaque OSCs.\nEspecially for the ST-module with an area above 100 cm2, the reported CTM of the 100\ncm2 ST-module is around 56%, which lags far behind the 100 cm2 opaque module\nreported in previous works (~ 88%).23, 24 In addition to inherent electric and geometric\nlosses of the module design, this performance gap primarily stems from the increased\nactive layer thickness during scaling up production, which reflects the fundamental\nchallenge of fabricating very thin film using scalable fabrication technologies. However,\nthe large active layer thickness leads to enhanced recombination, poor charge extraction,\nand reduced transmittance, resulting in exacerbated degradation of LUE for ST-OSCs.25,\nimprove the film thickness tolerance for preparing high-performance upscaling ST-\nmodules.27”\n On page 21 in the References Section of the revised Manuscript file:\n31\n25. Wang, G., Adil, M. A., Zhang, J. & Wei, Z. Large-area organic solar cells: material\nrequirements, modular designs, and printing methods. Adv. Mater. 31, e1805089 (2019).\n26. Chen, H. et al. Organic solar cells with 20.82% efficiency and high tolerance of\nactive layer thickness through crystallization sequence manipulation. Nat. Mater. 24,\n444-453 (2025).\n• Transmittance spectra and photographs of the cells are given in the Supporting\nInformation, but not in the main text. I think they are relevant for the content of the\nmanuscript and at least some of the spectra should be moved to the main manuscript.\nOn the other hand, some of the details shown in Figure 4 could go to the Supporting\nInformation.\nAuthor reply: Thanks very much for the reviewer’s suggestion. Firstly, the\ntransmittance spectra of small-area and large-area ST-devices with different active layer\nthicknesses have been added to Fig. 1g to enhance the completeness of the discussions\non device performance. The sub-figure labels of Fig. 1 in the main text (pages 4-6 in\nthe revised manuscript) have been updated due to the introduction of the transmittance\nspectra. Secondly, the data from Fig. 4e-f in the original manuscript have been relocated\nto Supplementary Fig. 35 to improve the figure clarity and streamline the main\nmanuscript, and the content of Fig. 4 has been reorganized. In addition, the photograph\nof 100 cm2 cell is added to the insert of Fig. 4b. The relevant revisions are shown as\nfollows:\n On pages 4-6 in the revised Manuscript file:\n“As seen in Fig. 1b-d and Supplementary Fig. 11, diluting donor content within the\nactive layer significantly reduces the absorption in the visible range, realizing high AVT\nin donor-diluted ST-OSCs.”\n“As shown in Fig. 1e, Supplementary Fig. 13, and Supplementary Table 8, we compared\nthe AVT of 1:1.5 and 1:3 active layers with different thicknesses.”\n“The current density (J)-voltage (V) curves and detailed parameters of ST-OSCs with\n“It is worth noting that the introduction of ARC improves the AVT of thick-film ST-\ndevices to more than 30% (Fig. 1g and Supplementary Fig. 10-12), indicating\noutstanding optical behaviors as shown in Supplementary Fig. 14.”\n“Besides, Fig. 1h and Supplementary Table 1 summarize the LUE values of reported\nlarge-area ST-OSCs with different thicknesses.”\n“Increasing thickness leads to a significant drop in the transmittance of the undiluted\ndevices (Fig. 1e), thereby reducing the LUE to around 2% or even below 1.5% for large-\narea ST-OSCs with thicknesses larger than 100 nm.”\nFig. 1|Device characteristics. a Chemical structures of PM6 and Qx-p-4Cl. b. The\nthickness-normalized absorption spectra of PM6:Qx-p-4Cl films. The device\nparameters statistics of (c) opaque and (d) semitransparent OSCs with different D:A\nratios. e The change of AVT against active layer thickness for spin-coated and slot-die-\n33\ncoated PM6:Qx-p-4Cl blends (△d represents the thickness difference between 1:1.5 and\n1:3 blends at the same transmittance). f The J-V curves of slot-die-coated ST-devices\nwith MoO ARC, and the insert shows the corresponding device architecture. g The\n3\ntransmittance spectra of small-area and large-area ST-devices. h The summary of LUE\nversus active layer thickness of reported large-area ST-OSCs (≥ 1 cm2).\n On page 14 in the revised Manuscript file:\n“Supplementary Fig. 35 provides the block diagrams of driving a liquid crystal display\n(LCD) screen and charging the 18650 lithium-ion battery system through the\nsemitransparent power-generating window, which is integrated into a scaled-down\nhouse model (Fig. 4e). When the model is transferred to the sunny outdoor environment,\nwe utilize the 600 cm2 power-generating window to simultaneously power a 4.3’’ LCD\nand a lithium-ion battery. It is worth noting that the screen can display artistic images\nwhen the VGA video signal is connected to the LCD (Supplementary Fig. 36 and\nSupplementary Video). On the other hand, the high acceptor content in the donor-\ndiluted blend can absorb more near-infrared (NIR) light, thereby effectively blocking\nthe NIR radiation and heat. The ST-module exhibits an excellent infrared radiation\nrejection (IRR) of 88.28%. As shown in Fig. 4f and Supplementary Fig. 37, another\nscale-down house model was exposed to the solar simulator to simulate the sunlight\nexposure.”\nenvironment. a The structure of the ST-module prepared in this work. b The J-V curves\nof 100 cm2 ST-module, and the insert figure shows the 100 cm2 ST-module. c The\nsummary of CTM versus the active layer area of the reported large-area ST-module.\nLUE\nd The schematic diagrams of practical applications verified in this work. e Photos of a\nscale-down house model with a 600 cm2 power-generating window that powers an LCD\nscreen and charges an 18650 lithium-ion battery. f The relationship between the\ntemperature inside the house model and irradiation time (the experiment is conducted\nwith a solar simulator under AM 1.5G conditions).\n On pages 3 and 22 in revised Supplementary file:\n“Supplementary Figure 35 | The block diagrams of applications of power generation.\nSupplementary Figure 36 | Photographs of applications of power generation.\nSupplementary Figure 37 | Photograph of ambient temperature.”\nstorage system.\n• If AVT values are given (for instance, on page 5), the corresponding spectrum should\nbe referenced.\nAuthor reply: Thanks very much for the reviewer’s suggestion. The corresponding\ntransmittance spectra have been referenced on page 5 of the revised manuscript as\nfollows:\n On page 5 in the revised Manuscript file:\n“As shown in Fig. 1e, Supplementary Fig. 13, and Supplementary Table 8, we compared\nthe AVT of 1:1.5 and 1:3 active layers with different thicknesses.”\n“It is worth noting that the introduction of ARC improves the AVT of thick-film ST-\ndevices to more than 30% (Fig. 1g and Supplementary Fig. 10-12), indicating\noutstanding optical behaviors as shown in Supplementary Fig. 14.”\n• The authors should perform a consistency check of EQE + Transmittance < 100% for\nat least some of the devices.\nAuthor reply: We thank the reviewer for the valuable comment. In addition to EQE\nand transmittance (T) spectra, the reflectance (R) spectra are also an important\nparameter for ST-OSCS. To further enhance the completeness of data, the reflectance\n(R) of three representative ST-OSCs (small-area semitransparent device, large-area\nsemitransparent devices with 119 and 180 nm thicknesses) was measured. Meanwhile,\nthe EQE+T+R spectra of these representative systems were also presented in\nto improve clarity and consistency of this manuscript. The related discussions and\nrevised figures have been shown in highlighted text on page 5 of the revised manuscript\nand revised Supplementary file as follows:\n On page 5 in the revised Manuscript file:\n“The corresponding EQE spectra are shown in Supplementary Fig. 10. The slot-die-\ncoated ST-device with a small active layer area (0.0256 cm2) yields a V of 0.87 V, J\nOC SC\nof 19.85 mA cm-2, FF of 71.66% and PCE of 12.37%. For large-area ST-OSCs with\ndifferent thicknesses, the 1 cm2 device with 180 nm active layer shows the highest PCE\nof 11.81%, along with a V of 0.89 V, J of 18.86 mA cm-2, and FF of 70.32%. When\nOC SC\nthe active layer thickness is increased to 301 nm, the PCE is slightly reduced to 11.25%.\nIt is worth noting that the introduction of ARC improves the AVT of thick-film ST-\ndevices to more than 30% (Fig. 1f and Supplementary Fig. 10-12), indicating\noutstanding optical behaviors as shown in Supplementary Fig. 14.”\n In revised Supplementary file:\nSupplementary Figure 10. The EQE spectra of slot-die-coated (a) PM6:P4Cl\n37\nsemitransparent devices with different D:A ratios, (b) MoO -midified PM6:Qx-p-4Cl\n3\n(1:3) semitransparent devices with different device area, and (c) larger active layer\nthickness. (d) The transmittance spectra of the MoO ARC-modified large-area\n3\nsemitransparent device with different active layer thickness.\nSupplementary Figure 12. The EQE, transmittance (T), reflection spectra (R), and\nEQE+T+R of MoO ARC-modified (a) small-area semitransparent device, (b) 119 nm,\n3\nand (c) 180 nm large-area semitransparent device.\n• If I understand correctly, the slot-die coated modules were fabricated with an\nevaporated silver top electrode and MoO3 layer. The latter is not really convenient for\nlarge-area production. Can the authors comment on this?\nAuthor reply: Thanks very much for the reviewer’s suggestion. The complexity of the\nevaporation process limits the application of MoO and metal electrodes in large-area\n3\nfabrication. However, the advantages of thermal evaporation, such as low defect density,\nhigh uniformity, excellent reproducibility, high yield, outstanding stability, etc., ensure\nreliable and efficient operation of the modules. More importantly, thermal evaporation\nenables the precise control of film thickness at the nanoscale, which is critical for\nsemitransparent organic solar cells. Because the efficiency and transmittance of a\nsemitransparent device are highly sensitive to film thickness. As a result, it is reasonable\nto adopt thermal evaporation for the fabrication of the MoO interlayer and the top\n3\nmetal electrode in our semitransparent module. The corresponding discussions were\nhighlighted on page 13 of the revised manuscript, and the related literature (Energy\nEnviron. Sci., 2025, 18, 5552) was cited as References 68 as follows:\n38\n On page 13 of the revised Manuscript file:\n“The inverted device structure of indium tin oxide (ITO)/zinc oxide nanoparticle (ZnO\nNP)/active layer/MoO /Ag/MoO is employed for module fabrication. Thermal\n3 3\nevaporation is used to deposit the MoO interlayer and top Ag electrode to enable\n3\nprecise control of film thickness.68 Because the efficiency and transmittance of ST-\nOSCs are highly sensitive to film thickness.7”\n On page 24 in the References Section of the revised Manuscript file:\n68. Jin, Z. et al. Fully evaporated interfacial layers for high-performance and batch-to-\nbatch reproducible organic solar modules. Energy Environ. Sci. 18, 5552-5563 (2025).\n• Since the authors highlight the applications of semitransparent OPV, they should\ninclude the operational stability of their modules.\nAuthor reply: Thanks very much for the reviewer’s suggestion. To further demonstrate\nthe application prospects of ST-SOCs in this work, we measured the operational\nstability of 1 cm2 large-area ST-OSCs and 100 cm2 ST-module. Firstly, we assessed the\nstability of 1 cm2 large-area ST-OSCs with a 1:3 D:A ratio under maximum power point\n(MPP) as shown in Supplementary Fig. 38, exposed to one sun illumination from an\nLED light source. The large-area device yields a T90 (retaining approximately 90% of\nthe initial efficiency) approaching 1000 h and an extrapolated T80 (retaining\napproximately 80% of the initial efficiency) exceeding 3100 h in the glove box,\nindicating excellent light stability in donor-diluted ST-OSCs. Secondly, the outdoor\nstability testing for the 100 cm2 ST-module was conducted to simulate real-world\noperating conditions better. We tracked the efficiency of the ST-module over the testing\nperiod, and weather data, including weather type, ambient temperature, and relative\nhumidity, were recorded simultaneously. As shown in Supplementary Fig. 38 and\nSupplementary Table 23, when the ST-module was exposed to the outdoor environment\nfor around 1000 h, the PCE dropped to 82.61% of its initial efficiency. The extrapolated\nT of the ST-module was calculated to 1500 h. This value is lower than that of 1 cm2\n39\nhas not yet reached an ideal state. As a result, donor-diluted ST-OSCs, including\nmonolithic devices and modules, yield high performance and long-term stability,\ndemonstrating excellent potential for practical applications. The relevant discussions\nand stability data were added to page 15 of the revised Manuscript file and the revised\nSupplementary file, respectively.\n On page 15 of the revised Manuscript file:\n“Device stability is also a key concern in the application of ST-OSCs. The photostability\nof 1 cm2 donor-diluted ST-OSCs (D:A = 1:3) was tested under one sun illumination in\na nitrogen atmosphere, as shown in Supplementary Fig. 38. The large-area device yields\nT (retains ca. 90% of the initial efficiency) approaching 1000 h and extrapolated T\n90 80\n(retains ca. 80% of the initial efficiency) exceeding 3100 h, indicating excellent\nphotostability in donor-diluted ST-OSCs. Furthermore, the outdoor stability testing for\nthe 100 cm2 ST-module was conducted to simulate real-world operating conditions\nbetter, and the weather data during the testing period were summarized in\nSupplementary Table 23. When the ST-module was exposed to the outdoor environment\nfor around 1000 h, the PCE dropped to 82.61% of its initial efficiency. It is worth noting\nthat the extrapolated T of the ST-module was calculated to 1500 h. As a result, donor-\n80\ndiluted ST-OSCs, including monolithic devices and modules, yield high performance\nand long-term stability, demonstrating excellent potential for practical applications.”\n On pages 3, 4, 24, and 33 in the revised Supplementary file:\n“Supplementary Figure 38 | Operational stability testing.”\n“Supplementary Table 23 | The summary of weather data during the stability testing\nperiod.”\n(D:A = 1:3) and 100 cm2 ST-module. (b) Normalized V , J , and FF with light-\nOC SC\nsoaking time for 1 cm2 ST-OSCs (D:A = 1:3).\nSupplementary Table 23. The summary of weather data during the outdoor stability\ntesting period.\nDate Weather Temperature (℃) Humidity (%)\nCloudy turning into\n2025/10/28-2025/11/3 1-18 25-60\nclear skies\nLight rain turning\n2025/11/4-2025/11/10 0-14 20-88\ninto clear skies\n2025/11/11-2025/11/17 Clear skies -4-17 17-39\n2025/11/18-2025/11/24 Clear skies -4-15 20-28\n2025/11/25-2025/12/1 Clear skies -6-9 17-37\n2025/12/2-2025/12/9 Clear skies -8-9 18-40\nReviewer #4 (Remarks to the Author):\nThe manuscript reports a donor-dilution strategy for fabricating thick-film slot-die-\ncoated ST-OSCs using non-halogenated solvents under ambient conditions. The authors\ndemonstrate devices with high efficiency, film thickness tolerance, and light utilization\n41\nefficiency, supported by mechanistic insights into aggregation and charge-generation\ndynamics. Furthermore, the approach is scaled to 100 cm² translucent module, which\nexhibits color quality and the practical potential of donor-diluted devices is validated\nthrough a 600 cm² power-generating window in a model house, thereby highlighting\ntheir relevance for BIPV applications. However, there are still some questions and\nissues that should be addressed.\n1. This manuscript lacks data on color rendering index and infrared rejection rate.\nWithout this information, it is difficult to evaluate the semitransparent and thermal\ninsulation performance quantitatively. Therefore, the authors should provide the\nfollowing relevant data: color rendering index, infrared rejection spectra and\ngeometrical fill factor.\nAuthor reply: We thank the reviewer for pointing out this issue. Firstly, the\ntransmittance spectrum of PM6:Qx-p-4Cl (D:A = 1:3) in the near-infrared range (830-\n2500 nm) was measured to obtain infrared radiation rejection (IRR), as shown in\nSupplementary Fig. 30b. The IRR is 88.28%. Secondly, the parameters of the color\nrendering index (CRI) and geometrical fill factor (GFF) of the ST-module were also\ncalculated. The ST-module exhibits CRI and GFF of 85% and 96.28%, respectively.\nThe transmittance spectrum in the near-infrared range and relevant discussions were\nadded in Supplementary Fig. 30b of the revised Supplementary file and pages 13-14 of\nthe revised manuscript, respectively.\n On pages 13-14 in the revised Manuscript file:\n“The width of the sub-cell is 4.5 mm, and the length between P1 and P3 is 174 μm, thus\nshowing a high geometric fill factor (GFF) of 96.28%.”\n“The 100 cm2 ST-module shows AVT of 31.97% and color rendering index (CRI) of\n85%, yielding an LUE of 3.32%.”\n“The ST-module exhibits an excellent infrared radiation rejection (IRR) of 88.28%.”\n42\n In revised Supplementary file:\nSupplementary Figure 30. (a) The transmittance spectrum of 100 cm2 ST-modules in\nthe visible range (400-800 nm). (b) The transmittance spectrum of PM6:Qx-p-4Cl (D:A\n= 1:3) in the near-infrared range (830-2500 nm) and the calculation of infrared radiation\nrejection (IRR).\n2. It is imperative to acknowledge the pivotal role of high carrier mobility in the\nfabrication of OSCs, particularly regarding their thickness tolerance. It is recommended\nthat the authors provide data on the electron and hole mobility of single-component and\nblend films. This will demonstrate the materials’ potential for use in the production of\nmodule devices with a thickness of approximately 300 nm.\nAuthor reply: Thanks very much for the reviewer’s suggestion. We measured the J-V\ncurves of hole- and electron-only devices and obtained the hole and electron mobilities\n(μ and μ ) via the space-charge-limited current (SCLC) method. As shown in\nhole electron\nSupplementary Fig. 15b, the high μ of neat Qx-p-4Cl (5.54 × 10-4 cm2 V-1 s-1) is\nelectron\nobserved. And the μ and μ of PM6:Qx-p-4Cl (1:3) are 6.95 × 10-4 and 5.79 ×\nhole electron\n10-4 cm2 V-1 s-1, respectively. The high carrier mobility ensures the high efficiency in\nthick-film devices, as shown in Supplementary Fig. 15a. In addition, the detailed\ncalculation method is added with highlight text on page 18 in the Methods Section of\nthe revised manuscript, and the relevant discussions are highlighted on page 6 of the\nrevised manuscript as follows:\n43\n On page 6 in the revised Manuscript file:\n“In contrast, the high carrier mobility (μ) of the P4Cl system (μ = 6.95×10-4 cm2 V-\nhole\n1 s-1, μ = 5.79×10-4 cm2 V-1 s-1) ensures high efficiency in thick-film devices as\nelectron\npresented in Supplementary Fig. 15. Importantly, as the thickness increases from 119\nnm to 301 nm, the LUE of the PM6:Qx-p-4Cl-based donor-diluted device decreases\nfrom 4.04% to 3.02%, exhibiting remarkable thickness tolerance.”\n On page 18 in the Methods Section of the revised Manuscript file:\n“The space-charge-limited current (SCLC) method is adopted to calculate carrier\nmobility. For SCLC fitting, the Mott-Gurney law (J = 9×ε ε μV2/8×L3) is used, where\n0 r\nε is the permittivity of materials (ε of 3 is selected in this work), ε is the vacuum\nr r 0\npermittivity (8.854×10-12 F/m), and L is the film thickness (L of 100 nm is used in this\nwork).”\n On pages 2 and 11 in the revised Supplementary file:\n“Supplementary Figure 15 | The PCE and LUE of ST-OSCs with different active layer\nthicknesses, and mobility calculation.”\nSupplementary Figure 15. (a) The PCE and LUE of large-area ST-OSCs with different\nthicknesses. (b) The J-V curves of electron-only device based on neat Qx-p-4Cl, hole-\nand electron-only devices based on PM6:Qx-p-4Cl (1:3).\n3. The manuscript contains some inaccuracies about the use and definition of certain\n44\nabbreviations. For instance, the abbreviation “CCL” should be “crystalline coherence\nlength” instead of “coherence length”. It is therefore recommended that authors\nundertake a systematic review of the entire manuscript to ensure that all abbreviations\nare accurately defined at first mention and used consistently throughout.\nAuthor reply: Thanks very much for the reviewer’s suggestion. We have updated\n“coherence length” to “crystalline coherence length” and conducted a systematic\nreview of all abbreviations in this manuscript. It was found that the definitions of the\nabbreviations of “ITO” and “LCD” were missing in the manuscript. The definitions of\nITO and LCD are indium tin oxide and liquid crystal display, respectively. The relevant\nupdates were highlighted on pages 7, 13, and 14 of the revised manuscript as follows:\n On page 7 in the revised Manuscript file:\n“The parameters of crystalline coherence length (CCL) and π-π stacking distance (d)\nwere extracted from GIWAXS patterns to gain deeper insight into molecular packing\nbehaviors.”\n On page 13 in the revised Manuscript file:\n“The inverted device structure of indium tin oxide (ITO)/zinc oxide nanoparticle (ZnO\nNP)/active layer/MoO /Ag/MoO is employed for module fabrication.”\n3 3\n On page 14 in the revised Manuscript file:\n“Supplementary Fig. 35 provides the block diagrams of driving a liquid crystal display\n(LCD) screen and charging the 18650 lithium-ion battery system through the\nsemitransparent power-generating window, which is integrated into a scaled-down\nhouse model (Fig. 4e).”\n4. The manuscript proposes that donor dilution lowers the viscosity of the BHJ solution,\nthereby accelerating the transition of the liquid film to a supersaturated state. However,\nthe lack of viscosity measurements for BHJ solutions with varying donor content\nhinders the robustness of this mechanistic explanation. The authors should therefore\nprovide corresponding viscosity data to support their claim.\nfurther strengthen our mechanistic interpretation, we measured the detailed viscosity of\nactive layer solutions with different D:A ratios via a viscometer (Brookfield, DV2T),\nas shown in Supplementary Table 18. The viscosity values of 1:0.5, 1:1, 1:1.5, 1:3, and\n1:5 are 5.95, 3.55, 2.91, 1.85, and 1.44 mPa s, respectively. It is indicated that diluting\nthe donor content significantly reduces the viscosity of the active layer solution, which\nis consistent with our analysis results. The detailed viscosity data were listed in\nSupplementary Table 18 of the revised Supplementary file. The relevant discussions\nand test information on viscosity were highlighted on pages 11, 12, and 19 of the revised\nmanuscript as follows:\n On pages 4 and 30 in the revised Supplementary file:\n“Supplementary Table 18 | The viscosity of PM6:Qx-p-4Cl with different D:A ratios.”\nSupplementary Table 18. The summary of the viscosity of PM6:Qx-p-4Cl with\ndifferent D:A ratios.\nD:A ratios Viscosity (mPa s)\n1:0.5 5.95\n1:1 3.55\n1:1.5 2.91\n1:3 1.85\n1:5 1.44\n On page 11 in the revised Manuscript file:\n“This difference is associated with solution viscosity, which is listed in Supplementary\nTable 18. Diluting donor content reduces the viscosity of the BHJ solution from 5.95\nmPa s at D:A ratio of 1:0.5 to 1.85 mPa s at 1:3, accelerating the process of the liquid\nfilm reaching supersaturation.”\n On page 12 in the revised Manuscript file:\n“As shown in Supplementary Table 18, the PM6:Qx-p-4Cl solutions with 1:1, 1:3, and\n46\n1:5 exhibit viscosity of 3.55, 1.85, and 1.33 mPa s, respectively.”\n On page 19 in the revised Manuscript file:\n“The viscosity data were measured via a viscometer (Brookfield, DV2T).”\n5. The photoluminescence quenching efficiency of the optimal D:A ratio of 1:3\nPM6:Qx-p-4Cl should be given to better demonstrate enough exciton dissociation.\nAuthor reply: Thanks very much for the reviewer’s suggestion. We measured the\nphotoluminescence (PL) spectra of neat Qx-p-4Cl and PM6:Qx-p-4Cl (1:3) blend to\ncalculate the corresponding photoluminescence quenching efficiency (PLQE). The\ncalculated PLQE of PM6:Qx-p-4Cl (1:3) blend is 90.75%, indicating efficient exciton\ndissociation. The PL spectra and relevant discussions were shown in Supplementary\nFig. 27a of the revised Supplementary file and highlighted text on page 9 of the revised\nmanuscript, respectively.\n On page 9 in the revised Manuscript file:\n“It is evident that the fibril widths in all the slot-die-coated PM6:Qx-p-4Cl films are\nsimilar (~ 21 nm), and the larger L of Qx-p-4Cl (22.34 nm) enables efficient exciton\nD\ndissociation, as confirmed by a photoluminescence quenching efficiency (PLQE) above\n90% (Supplementary Fig. 27).”\n In revised Supplementary file:\nSupplementary Figure 27. (a) The PL spectra of neat Qx-p-4Cl and PM6:Qx-p-4Cl\n(1:3) blend for calculation of PL quenching efficiency (PLQE). The (b) PL and (c)\nTRPL spectra of PM6:Qx-p-4Cl blends with different D:A ratios.\n47\n6. The manuscript proposes that donor dilution reduces solution viscosity and thereby\ninfluences film formation dynamics. While low-viscosity solutions have been shown to\nenhance leveling, accelerated drying may induce Marangoni flows or abnormal phase\nseparation, which could potentially compromise the continuity of the film. The\nsuppression of Marangoni effects is widely recognized as a key factor in achieving\nfavorable morphology. However, the absence of discussion on this aspect, as well as\nthe lack of direct supporting evidence, weakens the mechanistic interpretation.\nAuthor reply: We thank the reviewer for pointing out this issue. Marangoni flows arise\nfrom surface tension gradients and play a critical role in film uniformity. During the\nnatural drying of slot-die-coated film, the low viscosity may induce Marangoni flow.\nAccording to our previous report (Solar RRL, 2023, 7, 2300349), employing the\nairflow-assisted method during the slot-die coating process can reduce the temperature\ngradient, weakening the surface tension gradient due to the temperature dependence of\nsurface tension. Therefore, the negative effects caused by Marangoni flows and the\ncoffee ring effect can be suppressed. In this work, we also adopted an airflow-assisted\nmethod to weaken the Marangoni effect, realizing an ideal morphology in donor-diluted\nactive layer as shown in Fig. 2c. The relevant discussions were added in highlight text\non page 12 of the revised manuscript as follows:\n On page 12 in the revised Manuscript file:\n“However, the low viscosity may induce Marangoni flows during natural drying,\ninfluencing the film continuity and morphology of the active layer.36 To avoid this issue,\nwe adopted an airflow-assisted method to reduce the temperature gradient, thereby\nsuppressing Marangoni flows and the coffee ring effect.”\nReviewer #2:\nThe authors have reasonably addressed the issues raised by this reviewer. I would like\nto recommend the publication of this manuscript. However, I would suggest the authors\nciting a recent paper on reporting state-of-the-art large-scale semitransparent organic\nsolar module: “Scalable Polymer for Large-area Semitransparent Organic\nPhotovoltaics” Joule 2025, DOI: 10.1016/j.joule.2025.102173.\nAuthor reply: Thanks very much for the reviewer’s suggestion. The literature\nrecommended has been incorporated on page 14 of the manuscript, and cited as\nReference 69.\n On page 14 in the Manuscript file:\nTo minimize the performance degradation caused by geometric loss, P1, P2, and P3\nwere laser scribed.69-72\n On pafe 26 in the Manuscript file:\n69. Xie, D. et al. Scalable polymer for large-area semitransparent organic photovoltaics.\nJoule 9, 102173 (2025).\nReviewer #3:\nThe authors have answered all my questions, and generally put a lof of effort into the\nrevisions, so in my opinion the manuscript should be published in Nature\nCommunications.\nThe only request that I still have is to add the absolute PCE values to the degradation\ncurve that is now shown in Figure S38, especially since this curve only shows one\nvariation. People often use devices with lower PCE for degradation studies, and these\nnumbers are relevant to really assess and compare operational lifetimes.\nAuthor reply: We thank the reviewer for pointing out this issue. The stability data\nincluding absolute PCE values have been added in Supplementary Fig. 38.\n49\n In Supplementary Information file:\nSupplementary Figure 38. (a) Normalized PCE with testing time for 1 cm2 ST-OSCs\n(D:A = 1:3) and 100 cm2 ST-module. (b) Normalized V , J , and FF with light-\nOC SC\nsoaking time for 1 cm2 ST-OSCs (D:A = 1:3).\nReviewer #4:\nI recommend accepting the revised manuscript. Some closely related work should also\nbe cited in references, e.g. Adv. Mater. 2024, 36, 2305367; Nano Energy, 2024, 121,\n109219; Adv. Energy Mater. 2025, 15, 2501819, etc.\nAuthor reply: Thanks very much for the reviewer’s suggestion. The recommended\nworks have been incorporated on page 14 of the manuscript, and cited as References\n70, 71, and 72, respectively.\n On page 14 in the Manuscript file:\nTo minimize the performance degradation caused by geometric loss, P1, P2, and P3\nwere laser scribed.69-72\n50\n On pafe 26 in the Manuscript file:\n70. Sharma, A. et al. Semitransparent organic photovoltaics utilizing intrinsic charge\ngeneration in non-fullerene acceptors. Adv. Mater. 36, e2305367 (2024).\n71. Albab, M. F. et al. High-performance semi-transparent organic solar cells driven by\nthe dipole-controlled optoelectrical response of bilateral self-assembled monolayer\nstrategy. Nano Energy 121, (2024).\n72. Xie, J. et al. Non‐halogenated solvent‐processed organic solar cells with efficiencies\nexceeding 20.0% and 110 cm2 modules exceeding 13% enabled by film‐forming\ndynamics engineering. Adv. Energy Mater. 15, (2025).\n51"}, {"round": 2, "reviewer_comments": {"reviewer_2": "The authors have reasonably addressed the issues raised by this reviewer. I would like to recommend the publication of this manuscript. However, I would suggest the authors citing a recent paper on reporting state-of-the-art large-scale semitransparent organic solar module: “Scalable Polymer for Large-area Semitransparent Organic Photovoltaics” Joule 2025, DOI: 10.1016/j.joule.2025.102173.", "reviewer_3": "The authors have answered all my questions, and generally put a lof of effort into the revisions, so in my opinion the manuscript should be published in Nature Communications.\nThe only request that I still have is to add the absolute PCE values to the degradation curve that is now shown in Figure S38, especially since this curve only shows one variation. People often use devices with lower PCE for degradation studies, and these numbers are relevant to really assess and compare operational lifetimes.", "reviewer_4": "I recommend accepting the revised manuscript. Some closely related work should also be cited in references, e.g. Adv. Mater. 2024, 36, 2305367; Nano Energy, 2024, 121, 109219; Adv. Energy Mater. 2025, 15, 2501819, etc."}, "author_response": "A point-by-point response to the remaining comments from reviewers\nReviewer #2:\nThe authors have reasonably addressed the issues raised by this reviewer. I would like\nto recommend the publication of this manuscript. However, I would suggest the authors\nciting a recent paper on reporting state-of-the-art large-scale semitransparent organic\nsolar module: “Scalable Polymer for Large-area Semitransparent Organic\nPhotovoltaics” Joule 2025, DOI: 10.1016/j.joule.2025.102173.\nAuthor reply: Thanks very much for the reviewer’s suggestion. The literature\nrecommended has been incorporated on page 14 of the manuscript, and cited as\nReference 69.\n On page 14 in the Manuscript file:\nTo minimize the performance degradation caused by geometric loss, P1, P2, and P3\nwere laser scribed.69-72\n On pafe 26 in the Manuscript file:\n69. Xie, D. et al. Scalable polymer for large-area semitransparent organic photovoltaics.\nJoule 9, 102173 (2025).\nReviewer #3:\nThe authors have answered all my questions, and generally put a lof of effort into the\nrevisions, so in my opinion the manuscript should be published in Nature\nCommunications.\nThe only request that I still have is to add the absolute PCE values to the degradation\ncurve that is now shown in Figure S38, especially since this curve only shows one\nvariation. People often use devices with lower PCE for degradation studies, and these\nnumbers are relevant to really assess and compare operational lifetimes.\nAuthor reply: We thank the reviewer for pointing out this issue. The stability data\nincluding absolute PCE values have been added in Supplementary Fig. 38.\n49\n In Supplementary Information file:\nSupplementary Figure 38. (a) Normalized PCE with testing time for 1 cm2 ST-OSCs\n(D:A = 1:3) and 100 cm2 ST-module. (b) Normalized V , J , and FF with light-\nOC SC\nsoaking time for 1 cm2 ST-OSCs (D:A = 1:3).\nReviewer #4:\nI recommend accepting the revised manuscript. Some closely related work should also\nbe cited in references, e.g. Adv. Mater. 2024, 36, 2305367; Nano Energy, 2024, 121,\n109219; Adv. Energy Mater. 2025, 15, 2501819, etc.\nAuthor reply: Thanks very much for the reviewer’s suggestion. The recommended\nworks have been incorporated on page 14 of the manuscript, and cited as References\n70, 71, and 72, respectively.\n On page 14 in the Manuscript file:\nTo minimize the performance degradation caused by geometric loss, P1, P2, and P3\nwere laser scribed.69-72\n50\n On pafe 26 in the Manuscript file:\n70. Sharma, A. et al. Semitransparent organic photovoltaics utilizing intrinsic charge\ngeneration in non-fullerene acceptors. Adv. Mater. 36, e2305367 (2024).\n71. Albab, M. F. et al. High-performance semi-transparent organic solar cells driven by\nthe dipole-controlled optoelectrical response of bilateral self-assembled monolayer\nstrategy. Nano Energy 121, (2024).\n72. Xie, J. et al. Non‐halogenated solvent‐processed organic solar cells with efficiencies\nexceeding 20.0% and 110 cm2 modules exceeding 13% enabled by film‐forming\ndynamics engineering. Adv. Energy Mater. 15, (2025).\n51"}]

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