Query: passivate RP perovskite

title: Enabling room temperature processed highly efficient and stable 2D Ruddlesden Popper perovskite solar cells with eliminated hysteresis by synergistic exploitation of additives and solvents
abstract: Herein we demonstrate the favorable synergistic effect of an NH4Cl additive and DMSO solvent on 2D perovskites that are synthesized at room temperature. Interestingly, we observe the spontaneous formation of 3D phases within either NH4Cl or DMSO treated 2D perovskites, which plays a pivotal role in facilitating charge transport. It is revealed that NH4Cl increases charge carrier lifetime and passivate trap states within the 3D phase while DMSO promotes 2D/3D inter phase charge transfer. These two competitive processes reach a delicate balance in DMSO and NH4Cl co treated devices, which deliver a maximum PCE up to 13.41% with excellent air stability and eliminated hysteresis. This is among the highest values reported for 2D RP perovskite (n 4) based planar solar cells, particularly via all low temperature solution fabrication.

title: A dual function enabled novel zwitterion to stabilize a Pb I framework and passivate defects for highly efficient inverted planar perovskite solar cells.
abstract: A novel zwitterion named bethanechol chloride (BTCC) was introduced to simultaneously stabilize a Pb I framework and passivate defects for efficient inverted perovskite solar cells. The BTCC assisted device yielded an elevated power conversion efficiency of 20.45% with an open circuit voltage of 1.14 V.

title: 2D Intermediate Suppression for Efficient Ruddlesden Popper (RP) Phase Lead Free Perovskite Solar Cells
abstract: 2D Ruddlesden Popper (2DRP) tin (Sn) perovskite solar cells (PSCs) play an irreplaceable role in advancing the commercialization of perovskite based photovoltaic devices due to their low toxicity a.

title: Exploring Inorganic Binary Alkaline Halide to Passivate Defects in Low Temperature Processed Planar Structure Hybrid Perovskite Solar Cells

title: Multifunctional potassium hexafluorophosphate passivate interface defects for high efficiency perovskite solar cells
abstract: The interface modulation between perovskite and carrier transport layers via an appropriate chemical bond is an effective way to achieve the promoted carrier extraction and the reduced charge recombination for high efficiency perovskite solar cells (PSCs) Here, a multifunctional material potassium hexafluorophosphate (KPF6) is employed as an effective interface material between SnO2 quantum dots (QDs) and perovskite. At perovskite side, KPF6 could react with perovskite through the strong hydrogen bonds between PF6 group and organic cations, which could re orientate or redistribute the organic cation groups. Meanwhile, KPF6 could react with SnO2 QD through the strong ionic bonds between PF6 group and Sn4+/Sn2+ at the SnO2 QD side, which could passivate the interface defects to suppress the non radiative recombination for the improved electron transferring. Consequently, a champion PCE over 21% comes from the PSCs with 0.5 mg/ml KPF6 treated the SnO2 QD/perovskite interface, and the devices maintain ~90% of initial PCEs after 720 h storage in dry air.

title: New 2 D Ruddlesden Popper (RP) layered perovskite based solar cells
abstract: Another class of materials that has proved to be highly promising for the fabrication of solar cells are perovskites, calcium titanium oxide minerals that can be extracted from the Earth's mantle in specific geographical regions. This includes 2 D Ruddlesden Popper (RP) perovskites, which have a unique structure that could enhance a device's environmental stability and optoelectronic properties, without significantly compromising its efficiency.

title: Highly efficient all inorganic perovskite solar cells with suppressed non radiative recombination by a Lewis base
abstract: All inorganic perovskite solar cells (PVSCs) have drawn increasing attention because of their outstanding thermal stability. However, their performance is still inferior than the typical organic inorganic counterparts, especially for the devices with p i n configuration. Herein, we successfully employ a Lewis base small molecule to passivate the inorganic perovskite film, and its derived PVSCs achieved a champion efficiency of 16.1% and a certificated efficiency of 15.6% with improved photostability, representing the most efficient inverted all inorganic PVSCs to date. Our studies reveal that the nitrile (C N) groups on the small molecule effectively reduce the trap density of the perovskite film and thus significantly suppresses the non radiative recombination in the derived PVSC by passivating the Pb exposed surface, resulting in an improved open circuit voltage from 1.10 V to 1.16 V after passivation. This work provides an insight in the design of functional interlayers for improving efficiencies and stability of all inorganic PVSCs. There has been a hot competition to optimize the device performance for all inorganic perovskite solar cells. Here Wang et al. employ a Lewis base molecule to suppresses the non radiative recombination in the inverted device and achieve a champion efficiency of 16.1%

title: High efficiency mesoscopic solar cells using CsPbI3 perovskite quantum dots enabled by chemical interface engineering.
abstract: All inorganic a CsPbI3 perovskite quantum dots (QDs) are attracting high interest as solar cell absorbers due to their appealing light harvesting properties and enhanced stability due to the absence of volatile organic constituents. Moreover, ex situ synthesized QDs significantly reduce the variability of the perovskite layer deposition process. However, it is highly challenging to incorporate a CsPbI3 QDs into mesoporous TiO2 (m TiO2) which constitutes the best performing electron transport material in state of the art perovskite solar cells. Herein, the m TiO2 surface is engineered using an electron rich cesium ion containing methyl acetate solution. As one effect of this treatment, the solid liquid interfacial tension at the TiO2 surface is reduced and the wettability is improved, facilitating the migration of the QDs into m TiO2. As a second effect Cs+ ions passivate the QD surface and promote the charge transfer at the m TiO2/QD interface, leading to an enhancement of the electron injection rate by a factor of three. In combination with an ethanol environment smoothing route significantly reducing the surface roughness of the m TiO2/QD layer, optimized devices exhibit highly reproducible power conversion efficiencies exceeding 13% The best cell with an efficiency of 14.32% (reverse scan) reaches a short circuit current density of 17.77 mA cm 2, which is an outstanding value for QD based perovskite solar cells.

title: Interfacial defects passivation using fullerene polymer mixing layer for planar structure perovskite solar cells with negligible hysteresis
abstract: Recently, planar structure perovskite solar cells processed by low temperature solution method have attracted tremendous attention. However, the interfacial carrier recombination limits the further improvement in efficiency and causes serious hysteresis. Therefore, the effective interface passivation techniques are necessary to further improve the efficiency of perovskite solar cells (PSCs) In this work, we demonstrate that an ultrathin mixture layer of PMMA:PCBM with the optimization ratio of 1:2 can effectively passivate defects at the electron transport layer/perovskite interface, thus significantly inhibiting the interfacial carrier recombination, contributing to the improved open circuit voltage (Voc) and negligible hysteresis effect.  PCBM mixture passivation layer elevates the Voc of triple cation perovskite (Cs0.05(FA0.85MA0.15)0.95Pb(I0.85Br0.15)3) solar cells by 40 mV, with champion device achieving a Voc of 1.17 V. The maximum efficiency of the passivated PSCs is 18.63% with negligible hysteresis. Moreover, the interfacial passivation method improves the long term stability of PSCs, which retains 82% initial performance after over 768 h of storage at room temperature. This passivation approach successfully provides an avenue for further improving the efficiency and stability of PSCs.

title: A Polymerization Assisted Grain Growth Strategy for Efficient and Stable Perovskite Solar Cells.
abstract: Intrinsically, detrimental defects accumulating at the surface and grain boundaries limit both the performance and stability of perovskite solar cells. Small molecules and bulkier polymers with functional groups are utilized to passivate these ionic defects but usually suffer from volatility and precipitation issues, respectively. Here, starting from the addition of small monomers in the PbI2 precursor, a polymerization assisted grain growth strategy is introduced in the sequential deposition method. With a polymerization process triggered during the PbI2 film annealing, the bulkier polymers formed will be adhered to the grain boundaries, retaining the previously established interactions with PbI2 After perovskite formation, the polymers anchored on the boundaries can effectively passivate undercoordinated lead ions and reduce the defect density. As a result, a champion power conversion efficiency (PCE) of 23.0% is obtained, together with a prolonged lifetime where 85.7% and 91.8% of the initial PCE remain after 504 h continuous illumination and 2208 h shelf storage, respectively.