Spatiotemporally Correlated Imaging of Interfacial Defects and Photocurrents in High Efficiency Triple-Cation Mixed-Halide Perovskites

Yu, Junxi1,2,3,4; Huang, Boyuan4; Zheng, Xue5; Wang, Huan5; Chen, Fang5; Xie, Shuhong2,3; Wang, Qingyuan1,6; Li, Jiangyu4,5

2022-03-01

10.1002/smll.202200523

Small   影响因子和分区

1613-6810

1613-6829

Triple-cation mixed-halide perovskites have attracted considerable attention due to their excellent photovoltaic properties and enhanced stability, though the power conversion efficiency (PCE) is still far below the theoretical expectation. In order to understand the microscopic mechanisms responsible for the gap, a Cs-0.05(FA(0.85)MA(0.15))(0.95)Pb(I0.85Br0.15)(3) (CsFAMA)-based solar cell with respectful efficiency over 20% is examined, and distinct high- and low-current regions are observed in photoconductive atomic force microscopy (pc-AFM) mapping. Simulations attribute the difference in local photocurrents to interfacial donor defect densities at the NiO/CsFAMA interface, which is supported by electrochemical strain microscopy (ESM) mapping, revealing a negative correlation between ionic defects and photocurrents. The interfacial defects can be further manipulated by external bias upon relaxation study, resulting in reduced photocurrents accompanied by topography change when positive ions are driven toward the NiO/CsFAMA interface. It is also observed that both structure variation and photocurrent degradation upon accelerated aging test initiate at grain boundaries, which gradually expand at the expense of grain interior, suggesting that ionic defects are most active at grain boundaries. These findings render a direct correlation between interfacial defects and photocurrents while revealing degradation evolution, and if such interfacial defects heterogeneity can be mitigated, PCE toward the theoretical limit with enhanced stability can be envisioned.

interfacial defects local photocurrent photoconductive atomic force microscopy sequential excitation electrochemical strain microscopy triple-cation mixed-halide perovskites

SCI ; EI

英语

通讯

National Natural Science Foundation of China[12192213,12102164,51772254] ; Shenzhen Science and Technology Innovation Committee[JCYJ20180507182257563] ; Key-Area Research and Development Program of Guangdong Province[2018B010109009] ; Guangdong Basic and Applied Basic Research Foundation["2017A030313342","2020A1515110989"] ; Leading Talents Program of Guangdong Province[2016LJ06C372]

Chemistry ; Science & Technology - Other Topics ; Materials Science ; Physics

Chemistry, Multidisciplinary ; Chemistry, Physical ; Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary ; Physics, Applied ; Physics, Condensed Matter

WOS:000766384700001

WILEY-V C H VERLAG GMBH

20221111774754

Efficiency ; Grain boundaries ; Mapping ; Nickel oxide ; Perovskite ; Perovskite solar cells ; Photoconductivity ; Photocurrents ; Testing ; Topography

Surveying:405.3 ; Minerals:482.2 ; Electricity: Basic Concepts and Phenomena:701.1 ; Solar Cells:702.3 ; Light/Optics:741.1 ; Inorganic Compounds:804.2 ; Production Engineering:913.1 ; Materials Science:951

Web of Science

1.Chengdu Univ, Inst Adv Study, Chengdu 610106, Peoples R China
2.Xiangtan Univ, Key Lab Low Dimens Mat & Applicat Technol, Minist Educ, Xiangtan 411105, Hunan, Peoples R China
3.Xiangtan Univ, Sch Mat Sci & Engn, Xiangtan 411105, Hunan, Peoples R China
4.Southern Univ Sci & Technol, Dept Mat Sci & Engn, Shenzhen 518055, Guangdong, Peoples R China
5.Chinese Acad Sci, Shenzhen Inst Adv Technol, Shenzhen Key Lab Nanobiomech, Shenzhen 518055, Guangdong, Peoples R China
6.Sichuan Univ, Coll Architecture & Environm, MOE Key Lab Deep Earth Sci & Engn, Chengdu 610065, Peoples R China

Yu, Junxi,Huang, Boyuan,Zheng, Xue,et al. Spatiotemporally Correlated Imaging of Interfacial Defects and Photocurrents in High Efficiency Triple-Cation Mixed-Halide Perovskites[J]. Small,2022,18.

Yu, Junxi.,Huang, Boyuan.,Zheng, Xue.,Wang, Huan.,Chen, Fang.,...&Li, Jiangyu.(2022).Spatiotemporally Correlated Imaging of Interfacial Defects and Photocurrents in High Efficiency Triple-Cation Mixed-Halide Perovskites.Small,18.

Yu, Junxi,et al."Spatiotemporally Correlated Imaging of Interfacial Defects and Photocurrents in High Efficiency Triple-Cation Mixed-Halide Perovskites".Small 18(2022).