Stabilizing Solution and Solid Phased Perovskite Towards High Performance Photovoltaic Devices with Superior Batch Stability and Consistency

Stabilizing Solution and Solid Phased Perovskite Towards High Performance Photovoltaic Devices with Superior Batch Stability and Consistency | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Stabilizing Solution and Solid Phased Perovskite Towards High Performance Photovoltaic Devices with Superior Batch Stability and Consistency Chun Cheng, Guihua Zhang, Deng Wang, Bowei Li, Qing Lian, Xinyi Zou, and 9 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6028970/v1 This work is licensed under a CC BY 4.0 License Status: Published Journal Publication published 30 Sep, 2025 Read the published version in Nature Communications → Version 1 posted You are reading this latest preprint version Abstract Fabricating high-performance perovskite solar cells (PSCs) with solution processing is conducive to low-cost commercial production, it is therefore rather critical to stabilize perovskite in both solution and solid phases. For this purpose, the speed-up ageing of perovskite solution in air was systematically studied and its severe spontaneous degradation was observed. To address this issue, we introduce 4-(trifluoromethyl)phenylhydrazine (TFPH) to modify the perovskite solution, which presented enhanced storage stability. Consequently, when the modified solution was used to prepare PSCs, we obtained much improved and well consistent power conversion efficiencies (PCEs, ~ 26.0%) regardless of the perovskite solution ageing time, as well as excellent operational stability, which maintains PCE ≥ 92% for 1830 hours. These remarkable results are attributed to the multiple functions of TFPH: a) inhibiting the degradation of perovskite; b) favoring the oriented crystallization; c) reducing trapping density, etc. This work substantially assists understanding and modification to perovskite degradation in both solution and solid phases. The excellent performance stability and consistency on the TFPH modified device batches is of great significance for commercial production of PSCs. Physical sciences/Energy science and technology/Renewable energy/Solar energy/Photovoltaics/Solar cells Physical sciences/Materials science/Materials for energy and catalysis/Solar cells perovskite solar cell solution ageing perovskite degradation performance stability and consistency Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Solution-processable metal halide perovskite solar cells (PSCs) have witnessed remarkable progress over the past decade, with power conversion efficiencies now approaching 27%. 1 This exceptional performance, combined with their low-temperature solution processability, makes PSCs a highly promising candidate for next-generation thin-film photovoltaics. 2–4 The solution-based fabrication method offers significant advantages, including low-cost production, compatibility with large-area and flexible substrates, and scalability for industrial manufacturing. However, the instability of perovskite precursor solutions remains a critical challenge, severely limiting the reproducibility and consistency of device performance during large-scale production. 5,6 Furthermore, as organic-inorganic hybrid materials, perovskites inherently exhibit relatively poor stability, with degradation occurring under both storage and operational conditions. These issues pose significant barriers to the industrialization of perovskite photovoltaic devices, underscoring the urgent need for strategies to enhance the stability of both perovskite solutions and solid-state films. The chemical stability of perovskite precursor solutions is a fundamental prerequisite for the scalable manufacturing of high-performance perovskite solar cells (IPSCs). For instance, devices fabricated from aged solutions typically exhibit significantly lower power conversion efficiencies (PCEs) compared to those prepared using fresh solutions. 7–9 This instability primarily stems from the proton loss in organic salts, such as methylammonium (MA + ) and formamidinium (FA + ), and the oxidation of halides. These reactions disrupt the delicate chemical equilibrium in the precursor solution, leading to deviations from the stoichiometric ratio required for the formation of high-quality perovskite films and high-efficiency devices. Specifically, MA + readily undergoes deprotonation to form MA 0 , which can further react with FA + to produce MFA + , while the proton loss from FAI compromises solution stability even in the absence of MA + . 10,11 Recently, FA-based perovskite has emerged as a highly promising material for photovoltaic devices due to its broad light absorption spectrum and exceptional thermal stability. 12–14 However, the practical application of FA-based perovskite is also significantly hindered by stability issues. These degradation mechanisms pose critical challenges to the long-term performance and durability of perovskite solar cells. Given the pivotal role of formamidinium iodide (FAI) as a predominant precursor in FA-based perovskite systems, a comprehensive investigation into its ageing process is of paramount importance. To address these challenges, significant efforts have been devoted to stabilizing perovskite solutions and films through additive engineering. 8,15–17 For example, Lewis bases, such as thiourea and dimethyl sulfoxide (DMSO), have been employed to coordinate with undercoordinated Pb 2+ ions, thereby suppressing halide oxidation and improving solution stability. 15,16 Additionally, acidic additives, such as hydroiodic acid (HI) and hypophosphorous acid (HPA), have been introduced to mitigate the deprotonation of organic cations and maintain the chemical balance of the precursor solution. 17 Despite these advancements, the selection of effective additives remains challenging, as they must not only inhibit deprotonation and oxidation but also avoid interfering with the crystallization kinetics and morphology of the perovskite films. Achieving this balance is critical for ensuring both the stability of the precursor solution and the optoelectronic quality of the resulting perovskite films. In this study, we conducted a systematic investigation into the aging process of FA-rich perovskite solutions, revealing their severe spontaneous degradation when exposed to air. To mitigate this issue, we introduced 4-(trifluoromethyl) phenylhydrazine (TFPH) as a stabilizer to modify the perovskite solution, which significantly enhanced its storage stability. Our findings indicate that TFPH serves multiple functional roles in modifying the perovskite film: a) it inhibits the degradation of the perovskite; b) it promotes oriented crystallization; and c) it reduces the trapping density, among other benefits. When the TFPH-modified solution was utilized for the fabrication of PSC devices, it consistently delivered high PCEs of approximately 26.0%, irrespective of the solution's aging duration. Furthermore, the TFPH-modified PSCs exhibited markedly improved stability and performance consistency across device batches. Notably, the operational stability of these devices was significantly enhanced, retaining 92% of their initial efficiency after 1830 hours under the ISOS-L-3 protocol. Results and discussion Given that the organic-cation deprotonation and iodide oxidation are the main instability sources in this perovskite system, 12 we first investigate the ageing process of the predominant perovskite precursors, namely formamidinium iodide (FAI). To accelerate the ageing process that happens in glove box, the FAI solution is exposed to the ambient atmosphere (22 ℃, relative humidity(RH) ≥ 60%) for 3 days. In the following, if not specified, the ageing condition is the same as above. Figure 1 a compares the 1 H NMR spectra of the fresh and the aged FAI solutions, where c 1 and c 2 are corresponded to -CH and -NH 2 groups in FA + , respectively. 16,18 It is found that the integral intensity of c 2 peak (A c2 ) drops from 4.03 (fresh) to 3.54 (aged), indicating an evident decrease in the concentration of FA + . There is a sharp and strong peak newly appearing at 3.8 ppm (water peak), which indicates the presence of water that comes from air and from the FA + deprotonation. The color change provides more degradation information on the ageing of the FAI solutions. The fresh FAI solution is colorless while the aged one (3 days) exhibited a light-yellow color, indicating the generation of I 2 . The absorption peak at 365 nm (Fig. 1 b) from UV-Vis spectrum can be assigned as I 3 − (the combination of I 2 and I − ) and this also confirms the presence of I 2 . 19,20 The above results imply that the degradation of FAI leads to HI and the following oxidation product of I 2 . 11 Similar experiments were carried out on the typical FA 0.95 Cs 0.5 PbI 3 perovskite solutions (Fig. 1 c); this perovskite composition is commonly used for high-performance PSCs. 21 As the perovskite solutions are always light-yellow similar to I 2 solution, the observation by naked eyes and UV-Vis tests were conducted on their I 2 extracted solutions by toluene. It is hardly to observe light-yellow (I 2 ) color in all the toluene solutions by naked eyes ( Figure S1 ). However, from their UV-Vis spectra, a relatively weak I 3 − peak appeared from the toluene solution, which was obtained from the aged FAI solution. From these above results, it is concluded that both FAI and the FA-rich perovskite solutions have the spontaneous degradation in air, which is resulted from the halide oxidation and organic-cation deprotonation. To mitigate the above degradation process, we introduce 4-(trifluoromethyl) phenylhydrazine (TFPH) as a stabilizer to the studied FAI and perovskite solutions. In the presence of TFPH, the aged FAI solution maintains colorless, accompanied with the disappearance of the I 2 (I 3 − ) absorption peak at 365 nm (Fig. 1 b). These features were the same as those of the fresh FAI solution and thus it is concluded that that TFPH can effectively inhibit FAI degradation. 19,20 Beside the FAI solution, TFPH also works well to stable the FA 0.95 Cs 0.5 PbI 3 perovskite solution. No absorption peak of I 3 − was observed in the TFPH modified aged perovskite solutions. The above results indicate the common effect of TFPH in inhibiting the degradation of FAI contained solutions. To quantify the inhibiting effect of TFPH on the degradation of perovskite solution, we further characterize the above perovskite solutions aged in air for 1–3 days. As the ageing/storage time increases, the integral intensity of c 2 peak (A c2 ) of the control solution (FA 0.95 Cs 0.5 PbI 3 solution without TFPH) rapidly decreases from 3.99 to 2.76 (Fig. 1 d). For the target solution (the TFPH modified FA 0.95 Cs 0.5 PbI 3 solution), A c2 only presents a slight decrease from 3.84 to 3.77 (Fig. 1 e). The above results again confirmed the inhibiting effect of TFPH on the oxidation of I − to I 2 in the perovskite solution. Moreover, a fast increased water peak that shifts from 3.3 to 3.8 ppm with the ageing time was observed for the control solution while there is a rather weak and less-shifted water peak appearing for the target solution. As these solutions are aged in air, the rather weak peak intensity in the target solution indicates the solution hardly absorb water from the air. Moreover, the water peak is rather sensitive to the change of H + concentration and the above distinct changes of water peaks in the control perovskite solution, including its integral intensity (A w ) and peak position, reveals water in the control solution mainly comes from the degradation of perovskite. The weak and stable water peak reveals the effective inhibition of TFPH on the deprotonation of FA + to FA 0 . The trends of two indicators (A c2 and A w ) with the ageing time were re-plot in Fig. 1 f for a better view. It is clear to show that as the ageing time increased, the target solution delivered minor change on the above two indicator values while the control one had dramatical changes, indicating that the introduced TFPH can effectively stabilize the perovskite solution. The underlying mechanism that the TFPH inhibits the degradation of perovskite solution requires in-depth investigation. We thus mixed TFPH and I 2 and observed the resultant reactants, which can be revealed by the new peaks in both 1 H and 13 C NMR spectra. It is interesting to find that as the I 2 /TFPH ratio increases from 0:1 to 10:1, the intermediate product of 4-trifluoromethylbenzoldiazonium (TFBD, peaks located at 7.31 and 7.75 ppm) presented firstly and then gradually decreased while the final product of 4-iodotrifluorotoluene (TFBI, peaks located at 7.5 and 8.0 ppm) appeared and saturated (Fig. 2 a and 2 b). The identification of TFBD and TFBI can be referred to the Figure S2 and S3 and the Mass spectrum of Fig. 2 c ( TFBI at 271.92 m/z ) . According to Fig. 2 b and Table S1 , TFPH was consumed out by reacting with I 2 when the I 2 /TFPH ratio reached 1:4 (Fig. 2 b and Table S1 ). The amount of TFBD increased firstly and began to decline at the I 2 /TFPH ratio of 1:4 while the amount of TFBI increased all along. The above results suggest that I 2 is preferred to react with TFPH to deliver the intermediate TFBD and the final product TFBI (Fig. 2 c). Through the above reactions, I 2 is effectively reduced to I − and further trapped as TFBI if I 2 concentration is further increases. Based on the results from Figs. 1 and 2 , the degradation and inhibition mechanisms of perovskite solution with TFPH are proposed as in Fig. 2 d and 2 e and reactions (1)–(5). The observation of N 2 gas release from the TFPH@I 2 DMF solution supports the above reactions ( Figure S4 ). Therefore, the main composition of perovskite, that is FAI, tends to degrade as I 2 , H 2 O, NH 3 and HCOOH by reacting with O 2 during the ageing process/storage (reactions (1)-(3)). These products, especially I 2 , are reported to reduce the quality of perovskite film and deteriorate the PSC performance. Upon the introduction of TFPH, I 2 is reduced back to HI, inhibiting the deprotonation of FAI to FA 0 and HI (the reverse reaction (1)). When I 2 is accumulated, TFPH can reduce I 2 through reactions (4) and (5), suggesting that TFPH has an enhanced I 2 removal ability. This shows that TFPH can not only inhibit the spontaneous degradation of perovskite, but also effectively eliminate harmful I 2 accumulated in the system, regardless of whether it is preexisting or later produced. From above, it is concluded that TFPH can effectively suppress the degradation of the perovskite solution. However, it is necessary, yet unknown, that how TFPH affects the quality of perovskite film. We thus comprehensively characterize and compared the perovskite films prepared with the fresh, the aged and the TFPH modified aged solutions (named as the control(fresh), control(aged) and target (TFPH modified and aged) films). It is found that the target film has the similar enlarged grain size as that of the control(fresh) film while the control(aged) film has a slightly reduced grain size, evidenced by both the top-view ( Figure S5 ) and cross-sectional SEM images (Fig. 3 a). Notedly, TFPH can facilitate the oriented growth of perovskite film. The X-ray diffraction (XRD) patterns in Fig. 3 b show that all the three studied samples have the similar results while the target and the control(fresh) films exhibit a larger I (001) /I (111) ratio (Fig. 3 c) than that of the control (aged) film. This suggests the introduction of TFPH to the perovskite solution can maintain the high crystallinity of perovskite film though the film is prepared with the aged solution. The grazing incidence X-ray diffraction (GIXRD) measurements are performed to characterize the strain in the above perovskite films. As the penetration depth/tilt angle increases, the diffraction peak (2q) shifts to lower values from the initial position of 31.5° for all the studied films ( Figure S6 ). This behavior delivers negative fitted slopes of 2q-sin 2 φ (Fig. 3 d), which indicates tensile strain in the films. 22 It is interesting to find that with the introduction of TFPH, the as-obtained perovskite film presents a decreased strain, which might be beneficial to improve device performance. Due to its large molecular size, TFPH is more likely to localize on the grain surface instead of merging into the perovskite lattice. 18 The decreased average roughness (R a ) obtained from atomic force microscopy (AFM, Figure S7 ) and high-resolution X-ray photoemission spectroscopy (XPS) of C 1s and F 1s signals confirm the presence of TFPH on the perovskite surface ( Figure S8 ). The larger shifting binding energies of the Pb 4f and I 3d spectra ( Figure S9a, b ) further confirm the stronger interaction between TFPH and perovskite. This enhanced interaction may be beneficial for reducing the notorious defects. All in all, the target film has large grain, high orientation, lower strain and strong surface TFPH molecular bonding; these merits may lead to decrease in overall defects concentration. We further conducted the space-charge-limited current (SCLC) characterization to qualify the trap density of these perovskite films. According to the trap-filled limit voltages ( V TFL ) (Fig. 3 e), the trap density ( n trap ) values are calculated as 1.03×10 15 , 1.09×10 15 , and 0.92×10 15 cm − 3 , corresponding to the control(fresh), control(aged) and target films, respectively ( Table S2 ). The lowest n trap of the target film is consistent with its high quality, even that it was prepared by the ageing solution. This result can be attributed to the two facts that 1) TFPH can significantly reduce the detrimental I 2 in the ageing solution and the as-prepared perovskite films as well; 2) TFPH can improve the crystallinity of perovskite film. As a consequent, the target film has a comparable UV-Vis absorption as that of the control(fresh) film ( Figure S9c ) and exhibits a stronger photoluminescence (PL) emission and a longer PL lifetime (Fig. 3 f, g, Table S3 ) than the two control films (fresh and aged). It is thus concluded that TFPH can improve the quality of perovskite film. Device performance based on the TFPH modified perovskite solutions It is anticipated to obtain high performance PSCs with the high-quality target perovskite films. For this purpose, we fabricated a series of devices based on the control and the target perovskite solutions at different ageing time. The device structure is illustrated in Fig. 4 a, 4 b and 4 c show the champion PCEs of the control and the target devices fabricated with the fresh perovskite solutions and the aged perovskite solutions. Compared to the control device with a PCE of 23.7%, the target device has a greatly enhanced PCE of 25.9%, which is achieved by the remarkable improvements on V oc (1.12 to 1.19 V) and FF (0.83 to 0.86). This result is consistent with the better quality of the target perovskite film that is modified by TFPH. Figure 4 d and Table 1 show the performance change of the control and the target batched devices with the ageing time of the perovskite solutions increases (up to 60 days). The PCE of the target device remains almost unchanged after 60 days of aging (only a 0.04% decrease), with a standard deviation consistently between ± 0.29% and ± 0.33%, indicating stable and uniform performance. In contrast, the PCE of the control device decreases significantly (6.17% drop), and its standard deviation increases over time (from ± 0.40% to ± 2.07%), indicating poor stability and consistency. This result shows that the introduction of TFPH in perovskite solution can effectively improve the stability and consistency of device batches, which is of great significance for commercial device production. The data statistics in Fig. 4 d is listed in Table S4-S5 for the convenience of readers. Moreover, it is found that the PCE degradation observed in the control device with the aged time comes from the sharp decline in J SC (Fig. 4 b), which is attributed to the accumulation of I 2 in the perovskite solution with the ageing time. We calculated the integrated J SC from external quantum efficiency (EQE) spectra where the control (fresh), control (aged 60 days) and target (aged 60 days) devices show 24.94, 20.67 and 24.93 mA cm − 2 , respectively (Fig. 4 e), with a negligible mismatch between the J-V and EQE measurements. Figure 4 f shows the steady-state power output (SPO) at the maximum power point voltage ( V MPP ). The control (fresh) and target (aged 60 days) devices demonstrated rather stable SPO of 23.7% and 25.6%, respectively, while the control (aged 60 days) device exhibited a gradually decreased SPO (initial value 21.1%) over time. These results suggest the introduction of TFPH is also helpful to inhibit the perovskite degradation at the operation conditions and thus greatly enhance the operation stability of the PSCs. Table 1 PCEs of the batched PSCs based on the control and target solutions 1 day 15 days 30 days 60 days Control Average 22.99 ± 0.40% 21.39 ± 0.74% 19.58 ± 1.12% 16.82 ± 2.07% Champion 23.71% 22.70% 21.74% 20.21% Target Average 25.66 ± 0.29% 25.67 ± 0.31% 25.67 ± 0.33% 25.62 ± 0.29% Champion 25.95% 25.98% 26.00% 25.91% To verify the above deduction, we conducted long-term stability assessments following the ISOS-L-3 testing protocols. The encapsulated PSCs were illuminated under continuous 1-Sun intensity at the maximum power point (MPP) at 65°C and 60% RH. As shown in Fig. 4 g, the target (aged 60 days) device still maintained 92% of its initial PCE ( T 92 ) after 1830 h, which is one of the best lifetimes in ISOS-L-3 assessments so far ( Table S7 ). In contrast, both the control (fresh) and the control (aged 60 days) devices present bad operation stability with fast decay on PCE. The above results are quite interesting as they suggest that TFPH can inhibit the degradation of perovskite film under the harsh operation conditions. This is achieved by the firmly bonded TFPH molecules on the surface of perovskite grains with the same mechanism that TFPH works in the aged perovskite solution and is manifested in Fig. 2 . Conclusion We reported that the FA-rich perovskite solution took the severe spontaneous degradation when stored/aged in air. The decomposition products, especially I 2 , reduce the quality of perovskite film and deteriorate the PSC performance. Accordingly, we applied 4-(trifluoromethyl)phenylhydrazine (TFPH) to stable the perovskite solution and enhance the quality of the as-modified perovskite film. As a result, we achieved a much improved and well consistent PCEs ~ 26.0%, regardless of the solution ageing time, and remarkable operational stability. Significantly, the TFPH modified PSCs present greatly improved stability and consistency on the performance of device batches. This work sheds light on the substantial understanding of the ageing behavior of perovskite in air and unveils the work mechanism of TFPH to modify perovskite in solution/solid phases, providing an effective strategy for promising commercial production in near future. Declarations Acknowledgements This work was supported by Basic Research Project of Science and Technology Plan of Shenzhen (Grant No. 20231115112954001), the National Natural Science Foundation of China (Grant No. 22305111, 22409130 and 52173171), the National Key Research and Development Project funding from the Ministry of Science and Technology of China (Grant No. 2021YFB3800101), Guangdong Basic and Applied Basic Research Foundation (Grant No. 2023B1515120031), and the Shenzhen Science and Technology Innovation Committee (Grant No. SGDX20230116091649013). The authors also acknowledge the supports received from Fundamental Research Funds for the Student Innovation Training Program (Grant Nos. 2022G01, 2022G02, 2023S03, 2023X01, 2023X02, 2023X03), Southern University of Science and Technology (SUSTech), and special funds for Cultivation of Guangdong College Students’ Scientific and Technological Innovation (Grant Nos. pdjh2022c0005, pdjh2023b0460 and pdjh2024c10910). The authors acknowledge H. Yi at the Southern University of Science and Technology and SUSTech Core Research Facilities for assistance in the characterization of perovskite films. Authors contribution G. Z. and Q. L. conceptualized the work. G. Z., D. W. and Q. L. fabricated and characterized solar cells. B. L., Q. L. and G. Z. wrote the manuscript. G. Z., X. Z. and K. F. conducted NMR measurement. D. L., Q. Y., G. M., J. L. and A.A. carried out film measurements and analyzed the data. Q. L., B. L., X. G., B. X. and C.C. acquired funding. All authors participated in revising and proofreading the final manuscript. Conflict of Interest The authors declare no conflict of interest. Data Availability Statement The data that support the findings of this study are available from the corresponding author upon reasonable request. References NREL, “Best Research-Cell Efficiencies,” can be found under https://www.nrel. gov/pv/assets/pdfs/best-research-cell-efficiencies.pdf, Accessed 2025. Li, Z. et al. Stabilized hole-selective layer for high-performance inverted pin perovskite solar cells. Science 382 , 284-289 (2023). Li, B. & Zhang, W. Improving the stability of inverted perovskite solar cells towards commercialization. Communications Materials 3 , 65, (2022). Ugur, E. et al. Enhanced cation interaction in perovskites for efficient tandem solar cells with silicon. Science 385 , 533-538 (2024). Ding, B. et al. Dopant-additive synergism enhances perovskite solar modules. Nature 628 , 299-305 (2024). Ding, Y. et al. 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Li, M. et al. Orientated crystallization of FA-based perovskite via hydrogen-bonded polymer network for efficient and stable solar cells. Nature communications 14 , 573 (2023). Shen, Y. et al. Functional Ionic Liquid Polymer Stabilizer for High‐Performance Perovskite Photovoltaics. Angewandte Chemie 135 , e202300690 (2023). Kim, G. Y. et al. Large tunable photoeffect on ion conduction in halide perovskites and implications for photodecomposition. Nature materials 17 , 445-449 (2018). Liu, S. et al. Stable Surface Contact with Tailored Alkylamine Pyridine Derivatives for High‐Performance Inverted Perovskite Solar Cells. Advanced Materials 37 , 2415100 (2025). Li, F. et al. Regulating surface termination for efficient inverted perovskite solar cells with greater than 23% efficiency. Journal of the American Chemical Society 142 , 20134-20142 (2020). Additional Declarations There is NO Competing Interest. Supplementary Files SuppXXInfo.docx Cite Share Download PDF Status: Published Journal Publication published 30 Sep, 2025 Read the published version in Nature Communications → Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6028970","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":428191617,"identity":"c088d1cb-9af6-43b8-802e-a694bd54195d","order_by":0,"name":"Chun 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Technology","correspondingAuthor":false,"prefix":"","firstName":"Qing","middleName":"","lastName":"Lian","suffix":""},{"id":428191622,"identity":"9ed7bad9-7a04-4b8d-b0c1-d7c2f8cf77af","order_by":5,"name":"Xinyi Zou","email":"","orcid":"","institution":"Southern University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Xinyi","middleName":"","lastName":"Zou","suffix":""},{"id":428191623,"identity":"40eb4366-1828-4672-863d-4f56632570e2","order_by":6,"name":"Dongyang Li","email":"","orcid":"https://orcid.org/0000-0003-3633-2050","institution":"Department of Electrical and Electronic Engineering, The Hong Kong Polytechnic University","correspondingAuthor":false,"prefix":"","firstName":"Dongyang","middleName":"","lastName":"Li","suffix":""},{"id":428191624,"identity":"bc44e6e7-e907-46ca-adf8-d46611c7111a","order_by":7,"name":"Qiming Yin","email":"","orcid":"https://orcid.org/0009-0002-9826-9480","institution":"Southern University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Qiming","middleName":"","lastName":"Yin","suffix":""},{"id":428191625,"identity":"4bc38591-a826-4024-a90b-19fe861b1960","order_by":8,"name":"Guojun Mi","email":"","orcid":"","institution":"Southern University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Guojun","middleName":"","lastName":"Mi","suffix":""},{"id":428191626,"identity":"7a56ab83-3b13-4887-8138-5490ba14da45","order_by":9,"name":"Jie Li","email":"","orcid":"","institution":"Southern University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Jie","middleName":"","lastName":"Li","suffix":""},{"id":428191627,"identity":"82dd697d-f6ec-45c3-9576-b1d650cda609","order_by":10,"name":"Kui Feng","email":"","orcid":"https://orcid.org/0000-0003-0198-3996","institution":"Southern University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Kui","middleName":"","lastName":"Feng","suffix":""},{"id":428191628,"identity":"d46cea8e-2172-4ea4-971b-ce63c57e8983","order_by":11,"name":"Abbas Amini","email":"","orcid":"https://orcid.org/0000-0002-7987-9243","institution":"Western Sydney University","correspondingAuthor":false,"prefix":"","firstName":"Abbas","middleName":"","lastName":"Amini","suffix":""},{"id":428191629,"identity":"bbcdd812-8260-47a5-94f0-ceedba0d16f7","order_by":12,"name":"Alex Jen","email":"","orcid":"https://orcid.org/0000-0002-9219-7749","institution":"City University of Hong Kong","correspondingAuthor":false,"prefix":"","firstName":"Alex","middleName":"","lastName":"Jen","suffix":""},{"id":428191630,"identity":"51aabce9-9229-4b9a-942d-f1771485bc3a","order_by":13,"name":"Xugang Guo","email":"","orcid":"https://orcid.org/0000-0001-6193-637X","institution":"Southern University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Xugang","middleName":"","lastName":"Guo","suffix":""},{"id":428191631,"identity":"0bab35eb-4a64-4dd7-8aab-eff8ecf7c08d","order_by":14,"name":"Baomin Xu","email":"","orcid":"https://orcid.org/0000-0002-2868-0613","institution":"Southern University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Baomin","middleName":"","lastName":"Xu","suffix":""}],"badges":[],"createdAt":"2025-02-14 08:55:34","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6028970/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6028970/v1","draftVersion":[],"editorialEvents":[{"content":"https://doi.org/10.1038/s41467-025-63776-6","type":"published","date":"2025-09-30T04:00:00+00:00"}],"editorialNote":"","failedWorkflow":false,"files":[{"id":78509673,"identity":"37b728fe-8873-485d-a420-8c5c12cca7de","added_by":"auto","created_at":"2025-03-14 09:18:58","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":247084,"visible":true,"origin":"","legend":"\u003cp\u003e\u003cstrong\u003eInvestigation of the ageing of FAI and perovskite solutions. \u003c/strong\u003ea) \u003csup\u003e1\u003c/sup\u003eH NMR spectra and b) the corresponding UV-Vis spectra of the fresh and aged FAI solutions in air. DMSO-d\u003csub\u003e6\u003c/sub\u003e is used for all \u003csup\u003e1\u003c/sup\u003eH NMR tests. The inset is the photograph of the FAI solutions in air. c) UV-Vis spectra of perovskite solutions. \u003csup\u003e1\u003c/sup\u003eH NMR spectra of the d) control and e) target perovskite solutions exposed to air for 1-3 days. (f) The percentage reduction of the integral area of c\u003csub\u003e2\u003c/sub\u003e and H\u003csub\u003e2\u003c/sub\u003eO were obtained from the \u003csup\u003e1\u003c/sup\u003eH NMR spectra.\u0026nbsp;\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-6028970/v1/3262e724ca451d3de276093b.png"},{"id":78509676,"identity":"b63f4726-4b2c-4032-bf51-adfa4f1e9e23","added_by":"auto","created_at":"2025-03-14 09:18:58","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":169788,"visible":true,"origin":"","legend":"\u003cp\u003eUnderlying the mechanism of inhibiting solution ageing by reducing I\u003csub\u003e2\u003c/sub\u003e. a) \u003csup\u003e1\u003c/sup\u003eH NMR spectra of TFPH and b) ratio of \u003csup\u003e1\u003c/sup\u003eH NMR peak area at different I\u003csub\u003e2\u003c/sub\u003e/TFPH ratios. c) Mass spectrum of I\u003csub\u003e2\u003c/sub\u003e/TFPH in MeOH. d) Photographs of the reaction results between I\u003csub\u003e2\u003c/sub\u003e and TFPH. e) Proposed reaction process of TFPH to inhibit the perovskite solution ageing.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-6028970/v1/17db170528debe0d4bce39c8.png"},{"id":78510376,"identity":"c591e146-2031-4972-9423-486e119bf8f3","added_by":"auto","created_at":"2025-03-14 09:26:58","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":692478,"visible":true,"origin":"","legend":"\u003cp\u003eCharacterizations of the studied perovskite films. a) Cross-sectional SEM images. b) XRD patterns. c) Enlarged XRD areas (13.3-25°) with the calculated peak ratio of (001)/(111). d) Strain analysis based on the 2θ-sin\u003csup\u003e2\u003c/sup\u003eφ method. b) Steady-state PL spectra. c) Time-resolved PL decays. g) Dark I-V curves of the hole-only devices.\u0026nbsp;\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-6028970/v1/a99a9a227a07021c0daf7b8b.png"},{"id":78510378,"identity":"c2509e47-5fb7-44f2-8851-fa80ba81db1a","added_by":"auto","created_at":"2025-03-14 09:26:58","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":669636,"visible":true,"origin":"","legend":"\u003cp\u003eDevice performance with or without TFPH. a) Schematic structure of the fabricated devices. b-c) \u003cem\u003eJ-V\u003c/em\u003e curves of perovskite solution at various ageing times. d) Statistic data of perovskite solution, stored in a glovebox, at various ageing times. (e) Corresponding EQE spectra. Note that the aged results were obtained from the devices based on the solution after 30-day ageing. (f) Stabilized power output (SPO) at a fixed bias of \u003cem\u003eV\u003c/em\u003e\u003csub\u003emax\u003c/sub\u003e. (g) Long-term operational stability under maximum power point tracking (MPPT) is determined by the perturb and observe method.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-6028970/v1/1263a1ed86c52cc8105ad3b1.png"},{"id":92567948,"identity":"bcbf5317-8b74-4bc4-b22d-691a13482db9","added_by":"auto","created_at":"2025-10-01 07:07:42","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2468271,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6028970/v1/4840f86e-19b5-4002-9c3e-252a4a101c78.pdf"},{"id":78509675,"identity":"472da4c7-2409-4218-88b4-39a02d3be40b","added_by":"auto","created_at":"2025-03-14 09:18:58","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":2138966,"visible":true,"origin":"","legend":"","description":"","filename":"SuppXXInfo.docx","url":"https://assets-eu.researchsquare.com/files/rs-6028970/v1/4d7041b94ea8851977ff2120.docx"}],"financialInterests":"There is \u003cb\u003eNO\u003c/b\u003e Competing Interest.","formattedTitle":"Stabilizing Solution and Solid Phased Perovskite Towards High Performance Photovoltaic Devices with Superior Batch Stability and Consistency","fulltext":[{"header":"Introduction","content":"\u003cp\u003eSolution-processable metal halide perovskite solar cells (PSCs) have witnessed remarkable progress over the past decade, with power conversion efficiencies now approaching 27%.\u003csup\u003e1\u003c/sup\u003e This exceptional performance, combined with their low-temperature solution processability, makes PSCs a highly promising candidate for next-generation thin-film photovoltaics.\u003csup\u003e2\u0026ndash;4\u003c/sup\u003e The solution-based fabrication method offers significant advantages, including low-cost production, compatibility with large-area and flexible substrates, and scalability for industrial manufacturing. However, the instability of perovskite precursor solutions remains a critical challenge, severely limiting the reproducibility and consistency of device performance during large-scale production.\u003csup\u003e5,6\u003c/sup\u003e Furthermore, as organic-inorganic hybrid materials, perovskites inherently exhibit relatively poor stability, with degradation occurring under both storage and operational conditions. These issues pose significant barriers to the industrialization of perovskite photovoltaic devices, underscoring the urgent need for strategies to enhance the stability of both perovskite solutions and solid-state films.\u003c/p\u003e \u003cp\u003eThe chemical stability of perovskite precursor solutions is a fundamental prerequisite for the scalable manufacturing of high-performance perovskite solar cells (IPSCs). For instance, devices fabricated from aged solutions typically exhibit significantly lower power conversion efficiencies (PCEs) compared to those prepared using fresh solutions.\u003csup\u003e7\u0026ndash;9\u003c/sup\u003e This instability primarily stems from the proton loss in organic salts, such as methylammonium (MA\u003csup\u003e+\u003c/sup\u003e) and formamidinium (FA\u003csup\u003e+\u003c/sup\u003e), and the oxidation of halides. These reactions disrupt the delicate chemical equilibrium in the precursor solution, leading to deviations from the stoichiometric ratio required for the formation of high-quality perovskite films and high-efficiency devices. Specifically, MA\u003csup\u003e+\u003c/sup\u003e readily undergoes deprotonation to form MA\u003csup\u003e0\u003c/sup\u003e, which can further react with FA\u003csup\u003e+\u003c/sup\u003e to produce MFA\u003csup\u003e+\u003c/sup\u003e, while the proton loss from FAI compromises solution stability even in the absence of MA\u003csup\u003e+\u003c/sup\u003e.\u003csup\u003e10,11\u003c/sup\u003e Recently, FA-based perovskite has emerged as a highly promising material for photovoltaic devices due to its broad light absorption spectrum and exceptional thermal stability.\u003csup\u003e12\u0026ndash;14\u003c/sup\u003e However, the practical application of FA-based perovskite is also significantly hindered by stability issues. These degradation mechanisms pose critical challenges to the long-term performance and durability of perovskite solar cells. Given the pivotal role of formamidinium iodide (FAI) as a predominant precursor in FA-based perovskite systems, a comprehensive investigation into its ageing process is of paramount importance.\u003c/p\u003e \u003cp\u003eTo address these challenges, significant efforts have been devoted to stabilizing perovskite solutions and films through additive engineering.\u003csup\u003e8,15\u0026ndash;17\u003c/sup\u003e For example, Lewis bases, such as thiourea and dimethyl sulfoxide (DMSO), have been employed to coordinate with undercoordinated Pb\u003csup\u003e2+\u003c/sup\u003e ions, thereby suppressing halide oxidation and improving solution stability.\u003csup\u003e15,16\u003c/sup\u003e Additionally, acidic additives, such as hydroiodic acid (HI) and hypophosphorous acid (HPA), have been introduced to mitigate the deprotonation of organic cations and maintain the chemical balance of the precursor solution.\u003csup\u003e17\u003c/sup\u003e Despite these advancements, the selection of effective additives remains challenging, as they must not only inhibit deprotonation and oxidation but also avoid interfering with the crystallization kinetics and morphology of the perovskite films. Achieving this balance is critical for ensuring both the stability of the precursor solution and the optoelectronic quality of the resulting perovskite films.\u003c/p\u003e \u003cp\u003eIn this study, we conducted a systematic investigation into the aging process of FA-rich perovskite solutions, revealing their severe spontaneous degradation when exposed to air. To mitigate this issue, we introduced 4-(trifluoromethyl) phenylhydrazine (TFPH) as a stabilizer to modify the perovskite solution, which significantly enhanced its storage stability. Our findings indicate that TFPH serves multiple functional roles in modifying the perovskite film: a) it inhibits the degradation of the perovskite; b) it promotes oriented crystallization; and c) it reduces the trapping density, among other benefits. When the TFPH-modified solution was utilized for the fabrication of PSC devices, it consistently delivered high PCEs of approximately 26.0%, irrespective of the solution's aging duration. Furthermore, the TFPH-modified PSCs exhibited markedly improved stability and performance consistency across device batches. Notably, the operational stability of these devices was significantly enhanced, retaining 92% of their initial efficiency after 1830 hours under the ISOS-L-3 protocol.\u003c/p\u003e"},{"header":"Results and discussion","content":"\u003cp\u003eGiven that the organic-cation deprotonation and iodide oxidation are the main instability sources in this perovskite system,\u003csup\u003e12\u003c/sup\u003e we first investigate the ageing process of the predominant perovskite precursors, namely formamidinium iodide (FAI). To accelerate the ageing process that happens in glove box, the FAI solution is exposed to the ambient atmosphere (22 ℃, relative humidity(RH)\u0026thinsp;\u0026ge;\u0026thinsp;60%) for 3 days. In the following, if not specified, the ageing condition is the same as above. Figure\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ea compares the \u003csup\u003e1\u003c/sup\u003eH NMR spectra of the fresh and the aged FAI solutions, where c\u003csub\u003e1\u003c/sub\u003e and c\u003csub\u003e2\u003c/sub\u003e are corresponded to -CH and -NH\u003csub\u003e2\u003c/sub\u003e groups in FA\u003csup\u003e+\u003c/sup\u003e, respectively.\u003csup\u003e16,18\u003c/sup\u003e It is found that the integral intensity of c\u003csub\u003e2\u003c/sub\u003e peak (A\u003csub\u003ec2\u003c/sub\u003e) drops from 4.03 (fresh) to 3.54 (aged), indicating an evident decrease in the concentration of FA\u003csup\u003e+\u003c/sup\u003e. There is a sharp and strong peak newly appearing at 3.8 ppm (water peak), which indicates the presence of water that comes from air and from the FA\u003csup\u003e+\u003c/sup\u003e deprotonation. The color change provides more degradation information on the ageing of the FAI solutions. The fresh FAI solution is colorless while the aged one (3 days) exhibited a light-yellow color, indicating the generation of I\u003csub\u003e2\u003c/sub\u003e. The absorption peak at 365 nm (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb) from UV-Vis spectrum can be assigned as I\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e (the combination of I\u003csub\u003e2\u003c/sub\u003e and I\u003csup\u003e\u0026minus;\u003c/sup\u003e) and this also confirms the presence of I\u003csub\u003e2\u003c/sub\u003e.\u003csup\u003e19,20\u003c/sup\u003e The above results imply that the degradation of FAI leads to HI and the following oxidation product of I\u003csub\u003e2\u003c/sub\u003e.\u003csup\u003e11\u003c/sup\u003eSimilar experiments were carried out on the typical FA\u003csub\u003e0.95\u003c/sub\u003eCs\u003csub\u003e0.5\u003c/sub\u003ePbI\u003csub\u003e3\u003c/sub\u003e perovskite solutions (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ec); this perovskite composition is commonly used for high-performance PSCs.\u003csup\u003e21\u003c/sup\u003e As the perovskite solutions are always light-yellow similar to I\u003csub\u003e2\u003c/sub\u003e solution, the observation by naked eyes and UV-Vis tests were conducted on their I\u003csub\u003e2\u003c/sub\u003e extracted solutions by toluene. It is hardly to observe light-yellow (I\u003csub\u003e2\u003c/sub\u003e) color in all the toluene solutions by naked eyes (\u003cb\u003eFigure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e\u003c/b\u003e). However, from their UV-Vis spectra, a relatively weak I\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e peak appeared from the toluene solution, which was obtained from the aged FAI solution. From these above results, it is concluded that both FAI and the FA-rich perovskite solutions have the spontaneous degradation in air, which is resulted from the halide oxidation and organic-cation deprotonation.\u003c/p\u003e \u003cp\u003eTo mitigate the above degradation process, we introduce 4-(trifluoromethyl) phenylhydrazine (TFPH) as a stabilizer to the studied FAI and perovskite solutions. In the presence of TFPH, the aged FAI solution maintains colorless, accompanied with the disappearance of the I\u003csub\u003e2\u003c/sub\u003e (I\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e) absorption peak at 365 nm (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003eb). These features were the same as those of the fresh FAI solution and thus it is concluded that that TFPH can effectively inhibit FAI degradation.\u003csup\u003e19,20\u003c/sup\u003e Beside the FAI solution, TFPH also works well to stable the FA\u003csub\u003e0.95\u003c/sub\u003eCs\u003csub\u003e0.5\u003c/sub\u003ePbI\u003csub\u003e3\u003c/sub\u003e perovskite solution. No absorption peak of I\u003csub\u003e3\u003c/sub\u003e\u003csup\u003e\u0026minus;\u003c/sup\u003e was observed in the TFPH modified aged perovskite solutions. The above results indicate the common effect of TFPH in inhibiting the degradation of FAI contained solutions.\u003c/p\u003e \u003cp\u003eTo quantify the inhibiting effect of TFPH on the degradation of perovskite solution, we further characterize the above perovskite solutions aged in air for 1\u0026ndash;3 days. As the ageing/storage time increases, the integral intensity of c\u003csub\u003e2\u003c/sub\u003e peak (A\u003csub\u003ec2\u003c/sub\u003e) of the control solution (FA\u003csub\u003e0.95\u003c/sub\u003eCs\u003csub\u003e0.5\u003c/sub\u003ePbI\u003csub\u003e3\u003c/sub\u003e solution without TFPH) rapidly decreases from 3.99 to 2.76 (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ed). For the target solution (the TFPH modified FA\u003csub\u003e0.95\u003c/sub\u003eCs\u003csub\u003e0.5\u003c/sub\u003ePbI\u003csub\u003e3\u003c/sub\u003e solution), A\u003csub\u003ec2\u003c/sub\u003e only presents a slight decrease from 3.84 to 3.77 (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ee). The above results again confirmed the inhibiting effect of TFPH on the oxidation of I\u003csup\u003e\u0026minus;\u003c/sup\u003e to I\u003csub\u003e2\u003c/sub\u003e in the perovskite solution. Moreover, a fast increased water peak that shifts from 3.3 to 3.8 ppm with the ageing time was observed for the control solution while there is a rather weak and less-shifted water peak appearing for the target solution. As these solutions are aged in air, the rather weak peak intensity in the target solution indicates the solution hardly absorb water from the air. Moreover, the water peak is rather sensitive to the change of H\u003csup\u003e+\u003c/sup\u003e concentration and the above distinct changes of water peaks in the control perovskite solution, including its integral intensity (A\u003csub\u003ew\u003c/sub\u003e) and peak position, reveals water in the control solution mainly comes from the degradation of perovskite. The weak and stable water peak reveals the effective inhibition of TFPH on the deprotonation of FA\u003csup\u003e+\u003c/sup\u003e to FA\u003csup\u003e0\u003c/sup\u003e. The trends of two indicators (A\u003csub\u003ec2\u003c/sub\u003e and A\u003csub\u003ew\u003c/sub\u003e) with the ageing time were re-plot in Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003ef for a better view. It is clear to show that as the ageing time increased, the target solution delivered minor change on the above two indicator values while the control one had dramatical changes, indicating that the introduced TFPH can effectively stabilize the perovskite solution.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe underlying mechanism that the TFPH inhibits the degradation of perovskite solution requires in-depth investigation. We thus mixed TFPH and I\u003csub\u003e2\u003c/sub\u003e and observed the resultant reactants, which can be revealed by the new peaks in both \u003csup\u003e1\u003c/sup\u003eH and \u003csup\u003e13\u003c/sup\u003eC NMR spectra. It is interesting to find that as the I\u003csub\u003e2\u003c/sub\u003e/TFPH ratio increases from 0:1 to 10:1, the intermediate product of 4-trifluoromethylbenzoldiazonium (TFBD, peaks located at 7.31 and 7.75 ppm) presented firstly and then gradually decreased while the final product of 4-iodotrifluorotoluene (TFBI, peaks located at 7.5 and 8.0 ppm) appeared and saturated (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ea and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb). The identification of TFBD and TFBI can be referred to the Figure S2 and S3 and the Mass spectrum of Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ec \u003cb\u003e(\u003c/b\u003eTFBI at 271.92 m/z\u003cb\u003e)\u003c/b\u003e.\u003c/p\u003e \u003cp\u003eAccording to Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb and \u003cb\u003eTable \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e\u003c/b\u003e, TFPH was consumed out by reacting with I\u003csub\u003e2\u003c/sub\u003e when the I\u003csub\u003e2\u003c/sub\u003e/TFPH ratio reached 1:4 (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003eb and \u003cb\u003eTable \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e\u003c/b\u003e). The amount of TFBD increased firstly and began to decline at the I\u003csub\u003e2\u003c/sub\u003e/TFPH ratio of 1:4 while the amount of TFBI increased all along. The above results suggest that I\u003csub\u003e2\u003c/sub\u003e is preferred to react with TFPH to deliver the intermediate TFBD and the final product TFBI (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ec). Through the above reactions, I\u003csub\u003e2\u003c/sub\u003e is effectively reduced to I\u003csup\u003e\u0026minus;\u003c/sup\u003e and further trapped as TFBI if I\u003csub\u003e2\u003c/sub\u003e concentration is further increases. Based on the results from Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e, the degradation and inhibition mechanisms of perovskite solution with TFPH are proposed as in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ed and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003ee and reactions (1)\u0026ndash;(5). The observation of N\u003csub\u003e2\u003c/sub\u003e gas release from the TFPH@I\u003csub\u003e2\u003c/sub\u003e DMF solution supports the above reactions (\u003cb\u003eFigure S4\u003c/b\u003e). Therefore, the main composition of perovskite, that is FAI, tends to degrade as I\u003csub\u003e2\u003c/sub\u003e, H\u003csub\u003e2\u003c/sub\u003eO, NH\u003csub\u003e3\u003c/sub\u003e and HCOOH by reacting with O\u003csub\u003e2\u003c/sub\u003e during the ageing process/storage (reactions (1)-(3)). These products, especially I\u003csub\u003e2\u003c/sub\u003e, are reported to reduce the quality of perovskite film and deteriorate the PSC performance. Upon the introduction of TFPH, I\u003csub\u003e2\u003c/sub\u003e is reduced back to HI, inhibiting the deprotonation of FAI to FA\u003csup\u003e0\u003c/sup\u003e and HI (the reverse reaction (1)). When I\u003csub\u003e2\u003c/sub\u003e is accumulated, TFPH can reduce I\u003csub\u003e2\u003c/sub\u003e through reactions (4) and (5), suggesting that TFPH has an enhanced I\u003csub\u003e2\u003c/sub\u003e removal ability. This shows that TFPH can not only inhibit the spontaneous degradation of perovskite, but also effectively eliminate harmful I\u003csub\u003e2\u003c/sub\u003e accumulated in the system, regardless of whether it is preexisting or later produced.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFrom above, it is concluded that TFPH can effectively suppress the degradation of the perovskite solution. However, it is necessary, yet unknown, that how TFPH affects the quality of perovskite film. We thus comprehensively characterize and compared the perovskite films prepared with the fresh, the aged and the TFPH modified aged solutions (named as the control(fresh), control(aged) and target (TFPH modified and aged) films). It is found that the target film has the similar enlarged grain size as that of the control(fresh) film while the control(aged) film has a slightly reduced grain size, evidenced by both the top-view (\u003cb\u003eFigure S5\u003c/b\u003e) and cross-sectional SEM images (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ea). Notedly, TFPH can facilitate the oriented growth of perovskite film. The X-ray diffraction (XRD) patterns in Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003eb show that all the three studied samples have the similar results while the target and the control(fresh) films exhibit a larger I\u003csub\u003e(001)\u003c/sub\u003e/I\u003csub\u003e(111)\u003c/sub\u003e ratio (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ec) than that of the control (aged) film. This suggests the introduction of TFPH to the perovskite solution can maintain the high crystallinity of perovskite film though the film is prepared with the aged solution.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe grazing incidence X-ray diffraction (GIXRD) measurements are performed to characterize the strain in the above perovskite films. As the penetration depth/tilt angle increases, the diffraction peak (2q) shifts to lower values from the initial position of 31.5\u0026deg; for all the studied films (\u003cb\u003eFigure S6\u003c/b\u003e). This behavior delivers negative fitted slopes of 2q-sin\u003csup\u003e2\u003c/sup\u003eφ (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ed), which indicates tensile strain in the films.\u003csup\u003e22\u003c/sup\u003e It is interesting to find that with the introduction of TFPH, the as-obtained perovskite film presents a decreased strain, which might be beneficial to improve device performance. Due to its large molecular size, TFPH is more likely to localize on the grain surface instead of merging into the perovskite lattice.\u003csup\u003e18\u003c/sup\u003e The decreased average roughness (R\u003csub\u003ea\u003c/sub\u003e) obtained from atomic force microscopy (AFM, \u003cb\u003eFigure S7\u003c/b\u003e) and high-resolution X-ray photoemission spectroscopy (XPS) of C 1s and F 1s signals confirm the presence of TFPH on the perovskite surface (\u003cb\u003eFigure S8\u003c/b\u003e). The larger shifting binding energies of the Pb 4f and I 3d spectra (\u003cb\u003eFigure S9a, b\u003c/b\u003e) further confirm the stronger interaction between TFPH and perovskite. This enhanced interaction may be beneficial for reducing the notorious defects. All in all, the target film has large grain, high orientation, lower strain and strong surface TFPH molecular bonding; these merits may lead to decrease in overall defects concentration.\u003c/p\u003e \u003cp\u003eWe further conducted the space-charge-limited current (SCLC) characterization to qualify the trap density of these perovskite films. According to the trap-filled limit voltages (\u003cem\u003eV\u003c/em\u003e\u003csub\u003eTFL\u003c/sub\u003e) (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ee), the trap density (\u003cem\u003en\u003c/em\u003e\u003csub\u003etrap\u003c/sub\u003e) values are calculated as 1.03\u0026times;10\u003csup\u003e15\u003c/sup\u003e, 1.09\u0026times;10\u003csup\u003e15\u003c/sup\u003e, and 0.92\u0026times;10\u003csup\u003e15\u003c/sup\u003e cm\u003csup\u003e\u0026minus;\u0026thinsp;3\u003c/sup\u003e, corresponding to the control(fresh), control(aged) and target films, respectively (\u003cb\u003eTable S2\u003c/b\u003e). The lowest \u003cem\u003en\u003c/em\u003e\u003csub\u003etrap\u003c/sub\u003e of the target film is consistent with its high quality, even that it was prepared by the ageing solution. This result can be attributed to the two facts that 1) TFPH can significantly reduce the detrimental I\u003csub\u003e2\u003c/sub\u003e in the ageing solution and the as-prepared perovskite films as well; 2) TFPH can improve the crystallinity of perovskite film. As a consequent, the target film has a comparable UV-Vis absorption as that of the control(fresh) film (\u003cb\u003eFigure S9c\u003c/b\u003e) and exhibits a stronger photoluminescence (PL) emission and a longer PL lifetime (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003ef, g, \u003cb\u003eTable S3\u003c/b\u003e) than the two control films (fresh and aged). It is thus concluded that TFPH can improve the quality of perovskite film.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e\u003cb\u003eDevice performance based on the TFPH modified perovskite solutions\u003c/b\u003e\u003c/h2\u003e \u003cp\u003eIt is anticipated to obtain high performance PSCs with the high-quality target perovskite films. For this purpose, we fabricated a series of devices based on the control and the target perovskite solutions at different ageing time. The device structure is illustrated in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ea, \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb and \u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ec show the champion PCEs of the control and the target devices fabricated with the fresh perovskite solutions and the aged perovskite solutions. Compared to the control device with a PCE of 23.7%, the target device has a greatly enhanced PCE of 25.9%, which is achieved by the remarkable improvements on \u003cem\u003eV\u003c/em\u003e\u003csub\u003e\u003cem\u003eoc\u003c/em\u003e\u003c/sub\u003e (1.12 to 1.19 V) and FF (0.83 to 0.86). This result is consistent with the better quality of the target perovskite film that is modified by TFPH. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ed and Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e show the performance change of the control and the target batched devices with the ageing time of the perovskite solutions increases (up to 60 days). The PCE of the target device remains almost unchanged after 60 days of aging (only a 0.04% decrease), with a standard deviation consistently between \u0026plusmn;\u0026thinsp;0.29% and \u0026plusmn;\u0026thinsp;0.33%, indicating stable and uniform performance. In contrast, the PCE of the control device decreases significantly (6.17% drop), and its standard deviation increases over time (from \u0026plusmn;\u0026thinsp;0.40% to \u0026plusmn;\u0026thinsp;2.07%), indicating poor stability and consistency. This result shows that the introduction of TFPH in perovskite solution can effectively improve the stability and consistency of device batches, which is of great significance for commercial device production. The data statistics in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ed is listed in \u003cb\u003eTable S4-S5\u003c/b\u003e for the convenience of readers. Moreover, it is found that the PCE degradation observed in the control device with the aged time comes from the sharp decline in \u003cem\u003eJ\u003c/em\u003e\u003csub\u003e\u003cem\u003eSC\u003c/em\u003e\u003c/sub\u003e (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eb), which is attributed to the accumulation of I\u003csub\u003e2\u003c/sub\u003e in the perovskite solution with the ageing time. We calculated the integrated \u003cem\u003eJ\u003c/em\u003e\u003csub\u003eSC\u003c/sub\u003e from external quantum efficiency (EQE) spectra where the control (fresh), control (aged 60 days) and target (aged 60 days) devices show 24.94, 20.67 and 24.93 mA cm\u003csup\u003e\u0026minus;\u0026thinsp;2\u003c/sup\u003e, respectively (Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ee), with a negligible mismatch between the \u003cem\u003eJ-V\u003c/em\u003e and EQE measurements. Figure\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003ef shows the steady-state power output (SPO) at the maximum power point voltage (\u003cem\u003eV\u003c/em\u003e\u003csub\u003eMPP\u003c/sub\u003e). The control (fresh) and target (aged 60 days) devices demonstrated rather stable SPO of 23.7% and 25.6%, respectively, while the control (aged 60 days) device exhibited a gradually decreased SPO (initial value 21.1%) over time. These results suggest the introduction of TFPH is also helpful to inhibit the perovskite degradation at the operation conditions and thus greatly enhance the operation stability of the PSCs.\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003ePCEs of the batched PSCs based on the control and target solutions\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"6\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c5\" colnum=\"5\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c6\" colnum=\"6\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e \u003cp\u003e1 day\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e \u003cp\u003e15 days\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c5\"\u003e \u003cp\u003e30 days\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c6\"\u003e \u003cp\u003e60 days\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eControl\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAverage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e22.99\u0026thinsp;\u0026plusmn;\u0026thinsp;0.40%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e21.39\u0026thinsp;\u0026plusmn;\u0026thinsp;0.74%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e19.58\u0026thinsp;\u0026plusmn;\u0026thinsp;1.12%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e16.82\u0026thinsp;\u0026plusmn;\u0026thinsp;2.07%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eChampion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e23.71%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e22.70%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e21.74%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e20.21%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\" morerows=\"1\" rowspan=\"2\"\u003e \u003cp\u003eTarget\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eAverage\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25.66\u0026thinsp;\u0026plusmn;\u0026thinsp;0.29%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25.67\u0026thinsp;\u0026plusmn;\u0026thinsp;0.31%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e25.67\u0026thinsp;\u0026plusmn;\u0026thinsp;0.33%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e25.62\u0026thinsp;\u0026plusmn;\u0026thinsp;0.29%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eChampion\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e25.95%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e25.98%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c5\"\u003e \u003cp\u003e26.00%\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c6\"\u003e \u003cp\u003e25.91%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003eTo verify the above deduction, we conducted long-term stability assessments following the ISOS-L-3 testing protocols. The encapsulated PSCs were illuminated under continuous 1-Sun intensity at the maximum power point (MPP) at 65\u0026deg;C and 60% RH. As shown in Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003eg, the target (aged 60 days) device still maintained 92% of its initial PCE (\u003cem\u003eT\u003c/em\u003e\u003csub\u003e92\u003c/sub\u003e) after 1830 h, which is one of the best lifetimes in ISOS-L-3 assessments so far (\u003cb\u003eTable S7\u003c/b\u003e). In contrast, both the control (fresh) and the control (aged 60 days) devices present bad operation stability with fast decay on PCE. The above results are quite interesting as they suggest that TFPH can inhibit the degradation of perovskite film under the harsh operation conditions. This is achieved by the firmly bonded TFPH molecules on the surface of perovskite grains with the same mechanism that TFPH works in the aged perovskite solution and is manifested in Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003c/div\u003e"},{"header":"Conclusion","content":"\u003cp\u003eWe reported that the FA-rich perovskite solution took the severe spontaneous degradation when stored/aged in air. The decomposition products, especially I\u003csub\u003e2\u003c/sub\u003e, reduce the quality of perovskite film and deteriorate the PSC performance. Accordingly, we applied 4-(trifluoromethyl)phenylhydrazine (TFPH) to stable the perovskite solution and enhance the quality of the as-modified perovskite film. As a result, we achieved a much improved and well consistent PCEs\u0026thinsp;~\u0026thinsp;26.0%, regardless of the solution ageing time, and remarkable operational stability. Significantly, the TFPH modified PSCs present greatly improved stability and consistency on the performance of device batches. This work sheds light on the substantial understanding of the ageing behavior of perovskite in air and unveils the work mechanism of TFPH to modify perovskite in solution/solid phases, providing an effective strategy for promising commercial production in near future.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was supported by Basic Research Project of Science and Technology Plan of Shenzhen (Grant No. 20231115112954001), the National Natural Science Foundation of China (Grant No. 22305111, 22409130 and 52173171), the National Key Research and Development Project funding from the Ministry of Science and Technology of China (Grant No. 2021YFB3800101), Guangdong Basic and Applied Basic Research Foundation (Grant No. 2023B1515120031), and the Shenzhen Science and Technology Innovation Committee (Grant No. SGDX20230116091649013). The authors also acknowledge the supports received from Fundamental Research Funds for the Student Innovation Training Program (Grant Nos. 2022G01, 2022G02, 2023S03, 2023X01, 2023X02, 2023X03), Southern University of Science and Technology (SUSTech), and special funds for Cultivation of Guangdong College Students’ Scientific and Technological Innovation (Grant Nos. pdjh2022c0005, pdjh2023b0460 and pdjh2024c10910). The authors acknowledge H. Yi at the Southern University of Science and Technology and SUSTech Core Research Facilities for assistance in the characterization of perovskite films.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthors contribution\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eG. Z. and Q. L. conceptualized the work. G. Z., D. W. and Q. L. fabricated and characterized solar cells. B. L., Q. L. and G. Z. wrote the manuscript. G. Z., X. Z. and K. F. conducted NMR measurement. D. L., Q. Y., G. M., J. L. and A.A. carried out film measurements and analyzed the data. Q. L., B. L., X. G., B. X. and C.C. acquired funding. All authors participated in revising and proofreading the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of Interest\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData Availability Statement\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe data that support the findings of this study are available from the corresponding author upon reasonable request.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eNREL, \u0026ldquo;Best Research-Cell Efficiencies,\u0026rdquo; can be found under https://www.nrel. gov/pv/assets/pdfs/best-research-cell-efficiencies.pdf, Accessed 2025.\u003c/li\u003e\n\u003cli\u003eLi, Z.\u003cem\u003e et al.\u003c/em\u003e Stabilized hole-selective layer for high-performance inverted pin perovskite solar cells. \u003cem\u003eScience\u003c/em\u003e \u003cstrong\u003e382\u003c/strong\u003e, 284-289 (2023).\u003c/li\u003e\n\u003cli\u003eLi, B. \u0026amp; Zhang, W. 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For this purpose, the speed-up ageing of perovskite solution in air was systematically studied and its severe spontaneous degradation was observed. To address this issue, we introduce 4-(trifluoromethyl)phenylhydrazine (TFPH) to modify the perovskite solution, which presented enhanced storage stability. Consequently, when the modified solution was used to prepare PSCs, we obtained much improved and well consistent power conversion efficiencies (PCEs, ~ 26.0%) regardless of the perovskite solution ageing time, as well as excellent operational stability, which maintains PCE\u0026thinsp;\u0026ge;\u0026thinsp;92% for 1830 hours. These remarkable results are attributed to the multiple functions of TFPH: a) inhibiting the degradation of perovskite; b) favoring the oriented crystallization; c) reducing trapping density, etc. This work substantially assists understanding and modification to perovskite degradation in both solution and solid phases. The excellent performance stability and consistency on the TFPH modified device batches is of great significance for commercial production of PSCs.\u003c/p\u003e","manuscriptTitle":"Stabilizing Solution and Solid Phased Perovskite Towards High Performance Photovoltaic Devices with Superior Batch Stability and Consistency","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2025-03-14 09:18:53","doi":"10.21203/rs.3.rs-6028970/v1","editorialEvents":[],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"nature-communications","isNatureJournal":true,"hasQc":false,"allowDirectSubmit":false,"externalIdentity":"NCOMMS","sideBox":"Learn more about [Nature Communications](http://www.nature.com/ncomms/)","snPcode":"","submissionUrl":"https://mts-ncomms.nature.com/","title":"Nature Communications","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"ejp","reportingPortfolio":"Nature Communications","inReviewEnabled":true,"inReviewRevisionsEnabled":false}}],"origin":"","ownerIdentity":"18ec8a6d-8376-43a4-b143-c38a2b2e7018","owner":[],"postedDate":"March 14th, 2025","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"published-in-journal","subjectAreas":[{"id":45619521,"name":"Physical sciences/Energy science and technology/Renewable energy/Solar energy/Photovoltaics/Solar cells"},{"id":45619522,"name":"Physical sciences/Materials science/Materials for energy and catalysis/Solar cells"}],"tags":[],"updatedAt":"2025-10-01T07:07:36+00:00","versionOfRecord":{"articleIdentity":"rs-6028970","link":"https://doi.org/10.1038/s41467-025-63776-6","journal":{"identity":"nature-communications","isVorOnly":false,"title":"Nature Communications"},"publishedOn":"2025-09-30 04:00:00","publishedOnDateReadable":"September 30th, 2025"},"versionCreatedAt":"2025-03-14 09:18:53","video":"","vorDoi":"10.1038/s41467-025-63776-6","vorDoiUrl":"https://doi.org/10.1038/s41467-025-63776-6","workflowStages":[]},"version":"v1","identity":"rs-6028970","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-6028970","identity":"rs-6028970","version":["v1"]},"buildId":"8U1c8b4HqxoKbykW_rLl7","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}