期刊
ADVANCED MATERIALS
卷 29, 期 43, 页码 -出版社
WILEY-V C H VERLAG GMBH
DOI: 10.1002/adma.201703451
关键词
halide migration; hybrid perovskites; nanoprobe X-ray fluorescence; nudged elastic band (NEB) and DFT computation; spatially resolved photoluminescence mapping
类别
资金
- University of California (UC) Carbon Neutrality Initiative
- UC San Diego startup funds
- Hellman Foundation
- European Research Council (ERC) under the European Union's Seventh Framework Programme/ERC [337328]
- Philips
- FOM
- U.S. Department of Energy, Office of Science, Basic Energy Sciences [DE-SC0012118]
- National Science Foundation [ACI-1053575]
- DOE Office of Science [DE-AC02-06CH11357]
- U.S. Department of Energy (DOE) [DE-SC0012118] Funding Source: U.S. Department of Energy (DOE)
Optoelectronic devices based on hybrid perovskites have demonstrated outstanding performance within a few years of intense study. However, commercialization of these devices requires barriers to their development to be overcome, such as their chemical instability under operating conditions. To investigate this instability and its consequences, the electric field applied to single crystals of methylammonium lead bromide (CH3NH3PbBr3) is varied, and changes are mapped in both their elemental composition and photo-luminescence. Synchrotron-based nanoprobe X-ray fluorescence (nano-XRF) with 250 nm resolution reveals quasi-reversible field-assisted halide migration, with corresponding changes in photoluminescence. It is observed that higher local bromide concentration is correlated to superior optoelectronic performance in CH3NH3PbBr3. A lower limit on the electromigration rate is calculated from these experiments and the motion is interpreted as vacancy-mediated migration based on nudged elastic band density functional theory (DFT) simulations. The XRF mapping data provide direct evidence of field-assisted ionic migration in a model hybrid-perovskite thin single crystal, while the link with photoluminescence proves that the halide stoichiometry plays a key role in the optoelectronic properties of the perovskite.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据