Enhanced carrier transport over grain boundaries in lead-free CH3NH3Sn(I1-xBrx)(3) (0 <= x <= 1) perovskite solar cells
- 주제(키워드) tin-based perovskite , grain boundary , grain size , band bending , charge separation and collection
- 주제(기타) Nanoscience & Nanotechnology; Materials Science, Multidisciplinary; Physics, Applied
- 설명문(일반) [Jo, William] Ewha Womans Univ, Dept Phys, Seoul 03760, South Korea; Ewha Womans Univ, New & Renewable Energy Res Ctr NREC, Seoul 03760, South Korea
- 등재 SCIE, SCOPUS
- 발행기관 IOP PUBLISHING LTD
- 발행년도 2019
- URI http://www.dcollection.net/handler/ewha/000000159936
- 본문언어 영어
- Published As http://dx.doi.org/10.1088/1361-6528/ab19dd
- PubMed https://pubmed.ncbi.nlm.nih.gov/30991362
초록/요약
This paper reports on grain boundary (GB) roles in lead-free tin halide perovskite thin films. Nano scale spatial mapping of charge separation efficiency in methylammonium tin halide (MASn(I1-xBrx)(3), MA = CH3NH3) thin films were constructed by Kelvin probe force microscopy and conductive atomic force microscopy (C-AFM). We observed downward band bending at GBs under dark conditions and higher surface photovoltage along the GBs, confirmed by C-AFM which showed high local current flows along the GBs. The band bending degree and local current intensity were affected by the Br/I ratio. Photo-generated carriers were more effectively separated and collected at GBs with increased Br content, and hysteresis was observed in Br-rich Sn-halide perovskite.
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