milerssliu/battery-device-data-qa huggingface dataset:
To address the challenges facing Li–S batteries, considerable efforts have been made to develop sulfur-based cathode composite materials, modify separators, protect Li anodes, and use conductive interlayers and/or novel electrolyte additives (Fig. 1b). These approaches have all yielded certain encouraging results. However, the above strategies often have variable effects on the performance of Li–S batteries, owing to the specificity and interdependency of the S8–Li2Sn–Li2S (solid–liquid–solid) multistage transformation. For example, the conductive interlayer introduced between the separator and cathode suppresses the migration of LiPSs, which also offers additional electron pathways that cover the top surface of the cathode. This performance enhances the use of active materials and reduces random deposition of Li2S on the surface of the Li anode, thereby restraining dendrite formation and improving the anode stability to a certain degree.

Question: What's the anode?
Answer: Li
To address the challenges facing Li–S batteries, considerable efforts have been made to develop sulfur-based cathode composite materials, modify separators, protect Li anodes, and use conductive interlayers and/or novel electrolyte additives (Fig. 1b). These approaches have all yielded certain encouraging results. However, the above strategies often have variable effects on the performance of Li–S batteries, owing to the specificity and interdependency of the S8–Li2Sn–Li2S (solid–liquid–solid) multistage transformation. For example, the conductive interlayer introduced between the separator and cathode suppresses the migration of LiPSs, which also offers additional electron pathways that cover the top surface of the cathode. This performance enhances the use of active materials and reduces random deposition of Li2S on the surface of the Li anode, thereby restraining dendrite formation and improving the anode stability to a certain degree.

Question: What's the electrolyte?
In summary, it's proposed that stacking few-layer Nb2CTx with Ti3C2Tx nanosheets into composite structures is a simple and effective approach to improve the electrochemical performance of Nb2CTx-based films for supercapacitors. The intercalated Ti3C2Tx nanosheets between Nb2CTx layers effectively increase the interlayer spacing of Nb2CTx layers and impede the self-restacking of Nb2CTx nanosheets, which are favorable for electrolyte ions to rapidly diffuse and transport in the hybrid electrodes. The optimized Ti3C2Tx/Nb2CTx films possess enhanced capacitive performance and rate performance. A gravimetric capacitance of 370 F g−1 can be delivered at 2 mV s−1 and 56.1% capacitance retention at a high scan rate of 200 mV s−1. The energy density of the assembled all-solid-state supercapacitors can reach 5.5 mW h g−1 at a power density of 141.4 mW g−1, and 1.1 mW h g−1 at a high power density of 2350.0 mW g−1. The all-solid-state supercapacitors presented good flexibility and long cycling life. The all-solid-state supercapacitor was also integrated with a flex sensor to fabricate a self-powered device, where the all-solid-state supercapacitor served as a stable power source unit to drive the flex sensor. The route to fabricate Ti3C2Tx/Nb2CTx hybrid films is also applicable for other M2CTx MXenes, for example, Ti2CTx and V2CTx, improving the application potential of MXenes in flexible supercapacitors and integrated electronic devices.

Question: What's the electrolyte?
Nowadays, carbon nanomaterials are considered as the most important supercapacitor electrode materials. But it's still a great challenge to design rational structures of carbon materials at both nano and micro scales to endow carbon electrode materials with outstanding electrochemical performance. Herein, a well-designed compressible and elastic N-doped porous carbon nanofiber aerogel (N-PCNFA) with hierarchical cellular structures in both the PAN/ZIF-8-based carbon nanofibers and the 3D carbon monolith was prepared by a simple method. A large specific surface area was obtained for the construction of abundant pore structures and a robust architecture was built by the introduction of mechanically reinforced structures, which would endow the N-PCNFA electrode material with a vast surface area for ion adsorption/desorption, plenty of short channels for electrolyte diffusion and stable frameworks during the charge/discharge process. N heteroatoms were also incorporated into the carbon material as active sites for faradaic redox reactions. Thus, the N-PCNFA electrodes exhibited superior electrochemical performance, with a high specific capacitance of 279 F g−1 at 0.5 A g−1, consisting of pseudocapacitance (∼46%) and electrochemical double-layer capacitance (∼54%), remarkable rate performance of 59% at 20 A g−1 and excellent long-term durability. Moreover, the simple and general strategy for construction of compressible and elastic porous carbon nanofiber aerogels with delicate microstructures is also applicable to other advanced functional materials for a wide range of applications.

Question: What's the electrolyte?
The mechanism of the one-cell, two-electrode decoupled water splitting using Ni(OH)2 as the relay is shown in Fig. 1a. For the H2 evolution step, H2O is reduced on the GEE and the Ni(OH)2 electrode is oxidized to NiOOH simultaneously. By reversing the current polarity, O2 is produced on the GEE by an anodic oxidation of OH−; meanwhile the NiOOH electrode is reduced to Ni(OH)2. The cyclic voltammogram (CV) curve of the Ni(OH)2 electrode tested at a scan rate of 1 mV s−1 using Ag/AgCl as the reference electrode is shown in Fig. 1b. One pair of redox peaks located at 0.423 V/0.238 V (vs. Ag/AgCl) can be indexed to the reversible Ni(OH)2/NiOOH processes, which is consistent with the potential of the Ni(OH)2 electrode in the HER and OER processes. In operation, the one-cell, two-electrode design requires a cell voltage of 0.17 V for the OER step and 1.52 V for the HER step (Fig. 1c). The different operating voltages of the cell for HER and OER steps are caused by the redox potential of the RE (NiOOH/Ni(OH)2), which is much closer to the potential for the OER than the HER. As shown in Fig. 1d, at a cell current of 100 mA, the two-step water splitting process can be reversibly cycled for 24 rounds in 8 hours without noticeable decay. The duration for each OER and HER step was 10 min and the duration can be extended up to 3.5 h before the RE was fully consumed (Fig. S6†). Interestingly, in each gas evolution cycle, after the OER step, there is always a potential drop in the following HER step (inset in Fig. 1d). Meanwhile the HER process does not show this kind of peak. Since the ORR requires lower potential than the HER, after the OER step, there is residual O2 trapped on the GEE or dissolved in the electrolyte, and the ORR occurs to consume this O2, which temporarily reduces the cell voltage.

Question: What's the electrolyte?
In summary, we developed a formation method of a Li protective artificial SEI layer to form a LiF and polymeric composite protection layer directly on lithium metal foil using the electrochemical reaction between the Li and the sacrificial PTFE film by using roll-pressing. The roll-press process is facile, cost-effective, eco-friendly and a mass and large-area scalable process. The composite protection layer composed of a LiF-rich layer and polyene/unsaturated fluoropolymer rich layer could significantly improve the electrochemical properties of LMBs. The LiF@Po protection layer provides a stable interface between the Li metal and the electrolyte, enabling improved Li plating/stripping behavior and ultra-long cycling stability in both the Li‖Li symmetric cell and Li‖LCO/Li‖NCM full cells. In particular, the full cell with the NCM-811 cathode and LiF@Po–Li anode exhibits reasonable electrochemical performance even with transition metal dissolution. The material design strategies presented here could provide important avenues for forming an artificial SEI layer in various applications not only in Li metal systems but also in other metal systems including sodium and potassium.

Question: What's the cathode?
Answer: NCM-811
In summary, we developed a formation method of a Li protective artificial SEI layer to form a LiF and polymeric composite protection layer directly on lithium metal foil using the electrochemical reaction between the Li and the sacrificial PTFE film by using roll-pressing. The roll-press process is facile, cost-effective, eco-friendly and a mass and large-area scalable process. The composite protection layer composed of a LiF-rich layer and polyene/unsaturated fluoropolymer rich layer could significantly improve the electrochemical properties of LMBs. The LiF@Po protection layer provides a stable interface between the Li metal and the electrolyte, enabling improved Li plating/stripping behavior and ultra-long cycling stability in both the Li‖Li symmetric cell and Li‖LCO/Li‖NCM full cells. In particular, the full cell with the NCM-811 cathode and LiF@Po–Li anode exhibits reasonable electrochemical performance even with transition metal dissolution. The material design strategies presented here could provide important avenues for forming an artificial SEI layer in various applications not only in Li metal systems but also in other metal systems including sodium and potassium.

Question: What's the anode?
Answer: LiF@Po–Li
In summary, we developed a formation method of a Li protective artificial SEI layer to form a LiF and polymeric composite protection layer directly on lithium metal foil using the electrochemical reaction between the Li and the sacrificial PTFE film by using roll-pressing. The roll-press process is facile, cost-effective, eco-friendly and a mass and large-area scalable process. The composite protection layer composed of a LiF-rich layer and polyene/unsaturated fluoropolymer rich layer could significantly improve the electrochemical properties of LMBs. The LiF@Po protection layer provides a stable interface between the Li metal and the electrolyte, enabling improved Li plating/stripping behavior and ultra-long cycling stability in both the Li‖Li symmetric cell and Li‖LCO/Li‖NCM full cells. In particular, the full cell with the NCM-811 cathode and LiF@Po–Li anode exhibits reasonable electrochemical performance even with transition metal dissolution. The material design strategies presented here could provide important avenues for forming an artificial SEI layer in various applications not only in Li metal systems but also in other metal systems including sodium and potassium.

Question: What's the electrolyte?
To evaluate the performances of 2D GeP nanosheet-based photodetectors at an exact wavelength, selected wavelengths of lights (350, 365, 380, 400, 475, 550 and 650 nm) were employed (Fig. 4) in 0.1, 0.5 and 1 M KOH electrolytes. It is clear to see that the photocurrent density values are greatly smaller than the values under simulated light because of inferior light irradiation. The photocurrent density and photoresponsivity show a similar trend to the results in a simulated light state. Notably, it is also shown that such 2D GeP nanosheet-based photodetectors exhibit a higher sensitivity at a short wavelength range, especially at 350, 365 and 380 nm (Fig. 4c, f and i) and the highest photoresponsivity is 187.5 μA W−1 at 380 nm wavelength, 0.6 V applied bias potential and in 0.5 M KOH electrolyte. The above photo-response results at different wavelengths are in strong agreement with the UV-Vis absorption spectrum in Fig. 1g. Such results demonstrate great potential for high-performance UV-Vis photodetector application.

Question: What's the electrolyte?
Answer: 0.1, 0.5 and 1 M KOH
To evaluate the performances of 2D GeP nanosheet-based photodetectors at an exact wavelength, selected wavelengths of lights (350, 365, 380, 400, 475, 550 and 650 nm) were employed (Fig. 4) in 0.1, 0.5 and 1 M KOH electrolytes. It is clear to see that the photocurrent density values are greatly smaller than the values under simulated light because of inferior light irradiation. The photocurrent density and photoresponsivity show a similar trend to the results in a simulated light state. Notably, it is also shown that such 2D GeP nanosheet-based photodetectors exhibit a higher sensitivity at a short wavelength range, especially at 350, 365 and 380 nm (Fig. 4c, f and i) and the highest photoresponsivity is 187.5 μA W−1 at 380 nm wavelength, 0.6 V applied bias potential and in 0.5 M KOH electrolyte. The above photo-response results at different wavelengths are in strong agreement with the UV-Vis absorption spectrum in Fig. 1g. Such results demonstrate great potential for high-performance UV-Vis photodetector application.

Question: What's the electrolyte?
Answer: 0.5 M KOH
The detailed preparation processes of positive electrodes can be found in previous work. The mass loading of active material was ∼3.0 mg cm−2 for positive electrodes. In 2032-type half cells, lithium foil was used as the anode. Pre-lithiated MCMB was utilized as the negative electrode in full cells. The electrolyte was 1 M LiPF6 dissolved in mixed solvents of DMC and EC (7:3 by volume). Galvanostatic charge–discharge was conducted using a LAND tester (CT-2001A). All electrochemical testing was performed at room temperature (25 °C).

Question: What's the anode?
Answer: lithium foil
The detailed preparation processes of positive electrodes can be found in previous work. The mass loading of active material was ∼3.0 mg cm−2 for positive electrodes. In 2032-type half cells, lithium foil was used as the anode. Pre-lithiated MCMB was utilized as the negative electrode in full cells. The electrolyte was 1 M LiPF6 dissolved in mixed solvents of DMC and EC (7:3 by volume). Galvanostatic charge–discharge was conducted using a LAND tester (CT-2001A). All electrochemical testing was performed at room temperature (25 °C).

Question: What's the electrolyte?
Answer: 1 M LiPF6
The stretchability was also tested through stretching the developed spring ssZIBs. First, a spring solid-state battery was prepared by sealing the cathode, anode, and CNF–PAM hydrogel electrolyte in a spring-type plastic tube. As shown in Fig. 3i, a digital clock was powered by the developed blue spring solid-state battery. As shown by the figure in Fig. 3j and k and the video provided in ESI III and IV,† the spring solid-state battery still worked well under repeated tension and contraction. This demonstrates the robust stability, high stretchability and flexibility of our ssZIBs.

Question: What's the cathode?
The stretchability was also tested through stretching the developed spring ssZIBs. First, a spring solid-state battery was prepared by sealing the cathode, anode, and CNF–PAM hydrogel electrolyte in a spring-type plastic tube. As shown in Fig. 3i, a digital clock was powered by the developed blue spring solid-state battery. As shown by the figure in Fig. 3j and k and the video provided in ESI III and IV,† the spring solid-state battery still worked well under repeated tension and contraction. This demonstrates the robust stability, high stretchability and flexibility of our ssZIBs.

Question: What's the anode?
The stretchability was also tested through stretching the developed spring ssZIBs. First, a spring solid-state battery was prepared by sealing the cathode, anode, and CNF–PAM hydrogel electrolyte in a spring-type plastic tube. As shown in Fig. 3i, a digital clock was powered by the developed blue spring solid-state battery. As shown by the figure in Fig. 3j and k and the video provided in ESI III and IV,† the spring solid-state battery still worked well under repeated tension and contraction. This demonstrates the robust stability, high stretchability and flexibility of our ssZIBs.

Question: What's the electrolyte?
Answer: CNF–PAM hydrogel
Flexible lithium-ion batteries have attracted extensive attentions in electronics. However, their practical applications are primarily limited by low open-circuit voltage and energy density. Herein, we report a novel surface/interface modification strategy to obtain electrolyte-phobic carbon nanotube film as the flexible current collector for foldable lithium-ion batteries. The as-assembled battery exhibits a high open-circuit voltage of 4.04 V and energy density of ~293 Wh kg-1 with excellent flexibility and stable cycle performance. The outstanding performance is ascribed to the electrolyte-phobic surface/interfacial layer of carbon nanotube film, which restrains the intercalation of lithium ions into carbon-based current collector. This work not only demonstrates a practical solution to appreciably revamp the voltage and energy density of flexible lithium-ion batteries, but more importantly, offers valuable insights in modifying the surface/interface chemistry of carbon-based current collectors for high-performance energy storage devices.

Question: What's the electrolyte?
The slurry for the electrocatalytic study was prepared by dispersing 10 mg active material and 5 mg Super P carbon in 250 μL isopropyl alcohol and 750 μL distilled water. After sonicating the solution for 15 minutes, 5 μL Nafion binder was added followed by further sonication for 30 minutes. Then, 5 μL of the slurry was drop-casted on a glassy carbon rotating ring disc electrode (RRDE). The electrocatalytic study was carried out at room temperature using a CH instrument (CHI700E) bipotentiostat using 0.1 M KOH as the electrolyte.

Question: What's the electrolyte?
Answer: 0.1 M KOH
For the first time, DBHF nanofibers are constructed as flexible cathodes for HZBs. The formation mechanism of the DBHF structure is probed and the relationships between the synthetic conditions and the structures of the products are carefully investigated. Moreover, the HZBs are fabricated based on the DBHF cathode, Zn nanosheet@carbon cloth anode and a polymer electrolyte. Benefitting from the unique structure, the hybrid battery achieves high energy/power density and long-term cycling stability. Moreover, the high flexibility and “air-charging” capability make it a good uninterrupted power source for flexible electronics in different environments (Fig. 1h and i).

Question: What's the cathode?
Answer: DBHF nanofibers
For the first time, DBHF nanofibers are constructed as flexible cathodes for HZBs. The formation mechanism of the DBHF structure is probed and the relationships between the synthetic conditions and the structures of the products are carefully investigated. Moreover, the HZBs are fabricated based on the DBHF cathode, Zn nanosheet@carbon cloth anode and a polymer electrolyte. Benefitting from the unique structure, the hybrid battery achieves high energy/power density and long-term cycling stability. Moreover, the high flexibility and “air-charging” capability make it a good uninterrupted power source for flexible electronics in different environments (Fig. 1h and i).

Question: What's the anode?
Answer: Zn nanosheet@carbon
For the first time, DBHF nanofibers are constructed as flexible cathodes for HZBs. The formation mechanism of the DBHF structure is probed and the relationships between the synthetic conditions and the structures of the products are carefully investigated. Moreover, the HZBs are fabricated based on the DBHF cathode, Zn nanosheet@carbon cloth anode and a polymer electrolyte. Benefitting from the unique structure, the hybrid battery achieves high energy/power density and long-term cycling stability. Moreover, the high flexibility and “air-charging” capability make it a good uninterrupted power source for flexible electronics in different environments (Fig. 1h and i).

Question: What's the electrolyte?
For the first time, DBHF nanofibers are constructed as flexible cathodes for HZBs. The formation mechanism of the DBHF structure is probed and the relationships between the synthetic conditions and the structures of the products are carefully investigated. Moreover, the HZBs are fabricated based on the DBHF cathode, Zn nanosheet@carbon cloth anode and a polymer electrolyte. Benefitting from the unique structure, the hybrid battery achieves high energy/power density and long-term cycling stability. Moreover, the high flexibility and “air-charging” capability make it a good uninterrupted power source for flexible electronics in different environments (Fig. 1h and i).

Question: What's the cathode?
Answer: DBHF
To gain more insight into the morphological changes on the electrodes, as well as the causes of mNMR < mechem, we performed spectral fittings to determine how the relative fractions of the peaks assigned to Li microstructures vs. “bulk metal” change upon plating. The spectra were deconvoluted by using two peaks around 245–252.5 ppm (“bulk metal”) and one peak at around 257.5–262.5 ppm corresponding to the microstructural peak (see an example in Fig. 2f and more detailed explanation in the ESI†). We note that previous work has shown both experimentally and with simulations that dendrites and structures growing away from the Li metal surface give rise to larger shift around 270 ppm compared to microstructures close to the surface. In the current study, the in situ PEEK capsule cell applies constant pressure within the cell and more compact structures form, leading to a narrower range of shifts. The observed shifts of the microstructure peaks (Fig. S1†) are thus similar for both electrolytes although the microstructures have very distinct morphologies as seen in the SEM figures (Fig. 2b).

Question: What's the electrolyte?
For small molecules, making composites with conductive fillers is one of the main strategies to enhance the rate capability. Decreasing the particle size, e.g., via ball-milling, is apparently another effective approach. Conjugated polymers should have better electron conductivity and potentially perform better than non-conductive small molecules. However, the performance of reported conjugated structures was generally moderate. We suppose that this is partly because non-optimal carbonate-based electrolytes were used with these materials.

Question: What's the electrolyte?
Answer: carbonate-based
The ITO-coated glass samples were cleaned with acetone, ethanol, and isopropanol, sequentially. The vacant assemblies were prepared by using two ITO-coated glass samples with and without WO3 layers, respectively, which were stacked with a 60 μm-thick Surlyn adhesive film. Then, two electrolyte inlets were drilled into the ITO-coated glass side without the WO3 layer. The prepared electrolyte was injected into the vacant assemblies, and the inlets were closed. All the working areas were of 2.34 cm2 (1.3 cm × 1.8 cm). Finally, the filled assemblies were subjected to UV irradiation at a wavelength of 360 nm for periods of 0, 5, 10, and 20 min.

Question: What's the electrolyte?
EIS experiments. The electrolyte 65 mM Na[FeIII-racEDDHA], 0.7 M Na2SO4, 155 mM borate pH 9, was reduced at the negative electrode to reach 50% SoC (determined by photometry), using the same setup outlined in the charge–discharge cycling experiments. Potassium ferro/ferricyanide at 50% SoC was directly prepared with 32.5 mM K3[FeIII(CN)6], 32.5 mM K4[FeII(CN)6], 0.7 M Na2SO4, 1 mM borate, pH 9. Three-electrode configuration with two CRLEs used as working and counter electrode and a reference electrode (Ag/AgCl 3 M KCl) were connected to a BioLogic VSP potentiostat. The impedance spectra were recorded from 3 × 104 Hz to 5 × 10−2 Hz. An AC amplitude of 100 mV was applied on top of a DC potential matching the open cell potential at 50% SoC. All electrodes used had a similar roving length (72 mm) and weight (0.23 g).

Question: What's the electrolyte?
Answer: 65 mM Na[FeIII-racEDDHA], 0.7 M Na2SO4, 155 mM borate pH 9
While selecting the optimal potential range for oxocarbon derivatives, it is important to know that poorly reversible transformations can occur, especially at high potentials. For example, it is known that oxidation products of rhodizonates dissolve in the electrolytes, causing a rapid capacity decay. For this reason, only four-electron reduction is considered suitable for the practical operation of rhodizonates.

Question: What's the electrolyte?