Lead halide perovskite solar cells(PSCs)have been rapidly developed in the past decade.Owing to its excellent power conversion efficiency with robust and low-cost fabrication,perovskite quickly becomes one of the most...Lead halide perovskite solar cells(PSCs)have been rapidly developed in the past decade.Owing to its excellent power conversion efficiency with robust and low-cost fabrication,perovskite quickly becomes one of the most promising candidates for the next-generation photovoltaic technology.With the development of PSCs,the interface engineering has witnessed its increasingly critical role in maximizing the device performance as well as the long-term stability,because the interfaces in PSCs are closely correlated with the defect management,carrier dynamics and surface passivation.This review focuses on interfacial modification between the perovskite active layer and the charge transport layer,as well as the recent advances on high-efficiency and stable PSCs driven by interface engineering strategies.The contributing roles of interface engineering in terms of defect passivation,inhibiting ion migration,optimization of energy band alignment and morphological control are discussed.Finally,based on the latest progress and advances,strategies and opportunities for the future research on interface engineering for PSCs are proposed to promote the development of perovskite photovoltaic technology.展开更多
Two-dimensional(2D) alternating cation(ACI) perovskite surface defects,especially dominant iodine vacancies(V_Ⅰ) and undercoordinated Pb^(2+),limit the performance of perovskite solar cells(PVSCs).To address the issu...Two-dimensional(2D) alternating cation(ACI) perovskite surface defects,especially dominant iodine vacancies(V_Ⅰ) and undercoordinated Pb^(2+),limit the performance of perovskite solar cells(PVSCs).To address the issue,1-butyl-3-methylimidazolium trifluoro-methane-sulfonate(BMIMOTF) and its iodide counterpart(BMIMI) are utilized to modify the perovskite surface respectively.We find that BMIMI can change the perovskite surface,whereas BMIMOTF shows a nondestructive and more effective defect passivation,giving significantly reduced defect density and suppressed charge-carrier nonradiative recombination.This mainly attributes to the marked passivation efficacy of OTF-anion on V_Ⅰ and undercoordinated Pb^(2+),rather than BMIMI^(+) cation.Benefiting from the rational surface-modification of BMMIMOTF,the films exhibit an optimized energy level alignment,enhanced hydrophobicity and suppressed ion migration.Consequently,the BMIMOTF-modified devices achieve an impressive efficiency of 21.38% with a record open-circuit voltage of 1.195 V,which is among the best efficiencies reported for 2D PVSCs,and display greatly enhanced humidity and thermal stability.展开更多
Lead selenide(PbSe)colloidal quantum dots(CQDs)are suitable for the development of the next-generation of photovoltaics(PVs)because of efcient multiple-exciton generation and strong charge coupling ability.To date,the...Lead selenide(PbSe)colloidal quantum dots(CQDs)are suitable for the development of the next-generation of photovoltaics(PVs)because of efcient multiple-exciton generation and strong charge coupling ability.To date,the reported high-efcient PbSe CQD PVs use spin-coated zinc oxide(ZnO)as the electron transport layer(ETL).However,it is found that the surface defects of ZnO present a difculty in completion of passivation,and this impedes the continuous progress of devices.To address this disadvantage,fuoride(F)anions are employed for the surface passivation of ZnO through a chemical bath deposition method(CBD).The F-passivated ZnO ETL possesses decreased densities of oxygen vacancy and a favorable band alignment.Benefting from these improvements,PbSe CQD PVs report an efciency of 10.04%,comparatively 9.4%higher than that of devices using sol-gel(SG)ZnO as ETL.We are optimistic that this interface passivation strategy has great potential in the development of solution-processed CQD optoelectronic devices.展开更多
Bulk and interface carrier nonradiative recombination losses impede the further improvement of power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs).It is highly necessary to develop multifunct...Bulk and interface carrier nonradiative recombination losses impede the further improvement of power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs).It is highly necessary to develop multifunctional strategy to minimize surface and interface nonradiative recombination losses.Herein,we report a bulk and interface defect passivation strategy via the synergistic effect of anions and cations,where multifunctional potassium sulphate(K_(2)SO_(4))is incorporated at SnO_(2)/perovskite interface.We find that K^(+)ions in K_(2)SO_(4)diffuse into perovskite layer and suppress the formation of bulk defects in perovskite films,and the SO_(4)^(2-)ions remain located at interface via the strong chemical interaction with SnO_(2)layer and perovskite layer,respectively.Through this synergistic modification strategy,effective defect passivation and improved energy band alignment are achieved simultaneously.These beneficial effects are translated into an efficiency increase from 19.45%to 21.18%with a low voltage deficit of0.53 V mainly as a result of boosted open-circuit voltage(V_(oc))after K_(2)SO_(4)modification.In addition,the K_(2)SO_(4)modification contributes to ameliorated stability.The present work provides a route to minimize bulk and interface nonradiative recombination losses for the simultaneous realization of PCE and stability enhancement by rational anion and cation synergistic engineering.展开更多
Alkali metal doping or sulfurization are commonly applied in Cu_(2)ZnSnSe_(4) (CZTSe) solar cell to improve the open-circuit voltage (VOC). However, alkali metal sulfide affording both alkali metal and sulfur is seldo...Alkali metal doping or sulfurization are commonly applied in Cu_(2)ZnSnSe_(4) (CZTSe) solar cell to improve the open-circuit voltage (VOC). However, alkali metal sulfide affording both alkali metal and sulfur is seldom to be studied, which restrains the development of kesterite solar cells. In this study, we evaporate Li_(2)S during selenization process and hope to provide both alkali metal and sulfur to CZTSe film. The result indicates that Li shows a gradient distribution near the surface of CZTSe film and the content of S is slight. The film quality is improved and the recombination at grain boundaries is decreased after Li_(2)S treatment. Besides, the bandgap of the absorber gets wider. Under the synergy of sulfur and lithium (mainly from lithium), the work function of the treated absorber gets higher and the conduction band offset (CBO) is in the ideal range. Combined with these contributions, the V_(OC) of the champion device treated by Li_(2)S dramatically increase by 120 mV. This study discloses that alkali metal brings the main effect on the performance of the kesterite solar cell even an alkali metal sulfide is evaporated, which deepens the understanding of sulfurization of CZTSe and also promote the progress of kesterite solar cells.展开更多
基金support from Sichuan Science and Technology Program(No.2018JY0015).
文摘Lead halide perovskite solar cells(PSCs)have been rapidly developed in the past decade.Owing to its excellent power conversion efficiency with robust and low-cost fabrication,perovskite quickly becomes one of the most promising candidates for the next-generation photovoltaic technology.With the development of PSCs,the interface engineering has witnessed its increasingly critical role in maximizing the device performance as well as the long-term stability,because the interfaces in PSCs are closely correlated with the defect management,carrier dynamics and surface passivation.This review focuses on interfacial modification between the perovskite active layer and the charge transport layer,as well as the recent advances on high-efficiency and stable PSCs driven by interface engineering strategies.The contributing roles of interface engineering in terms of defect passivation,inhibiting ion migration,optimization of energy band alignment and morphological control are discussed.Finally,based on the latest progress and advances,strategies and opportunities for the future research on interface engineering for PSCs are proposed to promote the development of perovskite photovoltaic technology.
基金financially supported by the National Natural Science Foundation of China (62174021 and 62104028)the Creative Research Groups of the National Natural Science Foundation of Sichuan Province (2023NSFSC1973)+7 种基金the Sichuan Science and Technology Program (MZGC20230008)the Natural Science Foundation of Sichuan Province (2022NSFSC0899)the China Postdoctoral Science Foundation (2021M700689)the Grant SCITLAB (20012) of Intelligent Terminal Key Laboratory of Sichuan ProvinceFundamental Research Funds for the Central Universities (ZYGX2019J054)the Guangdong Basic and Applied Basic Research Foundation (2019A1515110438)sponsored by the University of Kentuckythe Sichuan Province Key Laboratory of Display Science and Technology。
文摘Two-dimensional(2D) alternating cation(ACI) perovskite surface defects,especially dominant iodine vacancies(V_Ⅰ) and undercoordinated Pb^(2+),limit the performance of perovskite solar cells(PVSCs).To address the issue,1-butyl-3-methylimidazolium trifluoro-methane-sulfonate(BMIMOTF) and its iodide counterpart(BMIMI) are utilized to modify the perovskite surface respectively.We find that BMIMI can change the perovskite surface,whereas BMIMOTF shows a nondestructive and more effective defect passivation,giving significantly reduced defect density and suppressed charge-carrier nonradiative recombination.This mainly attributes to the marked passivation efficacy of OTF-anion on V_Ⅰ and undercoordinated Pb^(2+),rather than BMIMI^(+) cation.Benefiting from the rational surface-modification of BMMIMOTF,the films exhibit an optimized energy level alignment,enhanced hydrophobicity and suppressed ion migration.Consequently,the BMIMOTF-modified devices achieve an impressive efficiency of 21.38% with a record open-circuit voltage of 1.195 V,which is among the best efficiencies reported for 2D PVSCs,and display greatly enhanced humidity and thermal stability.
基金the National Natural Science Foundation of China(Grant No.62105110)the Wuhan Institute of Technology(No.19QD09)the Analytical and Testing Center of HUST and the facility support of the Center for Nanoscale Characterization and Devices(CNCD),WNLO-HUST.
文摘Lead selenide(PbSe)colloidal quantum dots(CQDs)are suitable for the development of the next-generation of photovoltaics(PVs)because of efcient multiple-exciton generation and strong charge coupling ability.To date,the reported high-efcient PbSe CQD PVs use spin-coated zinc oxide(ZnO)as the electron transport layer(ETL).However,it is found that the surface defects of ZnO present a difculty in completion of passivation,and this impedes the continuous progress of devices.To address this disadvantage,fuoride(F)anions are employed for the surface passivation of ZnO through a chemical bath deposition method(CBD).The F-passivated ZnO ETL possesses decreased densities of oxygen vacancy and a favorable band alignment.Benefting from these improvements,PbSe CQD PVs report an efciency of 10.04%,comparatively 9.4%higher than that of devices using sol-gel(SG)ZnO as ETL.We are optimistic that this interface passivation strategy has great potential in the development of solution-processed CQD optoelectronic devices.
基金financially supported by the Defense Industrial Technology Development Program(JCKY2017110C0654)the National Natural Science Foundation of China(11974063,61904023)the Chongqing Special Postdoctoral Science Foundation(cstc2019jcyj-bsh0026)。
文摘Bulk and interface carrier nonradiative recombination losses impede the further improvement of power conversion efficiency(PCE)and stability of perovskite solar cells(PSCs).It is highly necessary to develop multifunctional strategy to minimize surface and interface nonradiative recombination losses.Herein,we report a bulk and interface defect passivation strategy via the synergistic effect of anions and cations,where multifunctional potassium sulphate(K_(2)SO_(4))is incorporated at SnO_(2)/perovskite interface.We find that K^(+)ions in K_(2)SO_(4)diffuse into perovskite layer and suppress the formation of bulk defects in perovskite films,and the SO_(4)^(2-)ions remain located at interface via the strong chemical interaction with SnO_(2)layer and perovskite layer,respectively.Through this synergistic modification strategy,effective defect passivation and improved energy band alignment are achieved simultaneously.These beneficial effects are translated into an efficiency increase from 19.45%to 21.18%with a low voltage deficit of0.53 V mainly as a result of boosted open-circuit voltage(V_(oc))after K_(2)SO_(4)modification.In addition,the K_(2)SO_(4)modification contributes to ameliorated stability.The present work provides a route to minimize bulk and interface nonradiative recombination losses for the simultaneous realization of PCE and stability enhancement by rational anion and cation synergistic engineering.
基金This work was supported by the National Key R&D Program of China(2018YFB1500200,2019YFB1503500)the National Natural Science Foundation of China(U1902218,11774187)the 111 Project(B16027).
文摘Alkali metal doping or sulfurization are commonly applied in Cu_(2)ZnSnSe_(4) (CZTSe) solar cell to improve the open-circuit voltage (VOC). However, alkali metal sulfide affording both alkali metal and sulfur is seldom to be studied, which restrains the development of kesterite solar cells. In this study, we evaporate Li_(2)S during selenization process and hope to provide both alkali metal and sulfur to CZTSe film. The result indicates that Li shows a gradient distribution near the surface of CZTSe film and the content of S is slight. The film quality is improved and the recombination at grain boundaries is decreased after Li_(2)S treatment. Besides, the bandgap of the absorber gets wider. Under the synergy of sulfur and lithium (mainly from lithium), the work function of the treated absorber gets higher and the conduction band offset (CBO) is in the ideal range. Combined with these contributions, the V_(OC) of the champion device treated by Li_(2)S dramatically increase by 120 mV. This study discloses that alkali metal brings the main effect on the performance of the kesterite solar cell even an alkali metal sulfide is evaporated, which deepens the understanding of sulfurization of CZTSe and also promote the progress of kesterite solar cells.
