Giant Light-Emission Enhancement in Lead Halide Perovskites by Surface Oxygen Passivation

• DOI: 10.1021/acs.nanolett.8b02887
• Publication Date: 2018-09-28T22:58:01Z
• Authors: Dylan Lu; Ye Zhang; Minliang Lai; Alex Lee; Chenlu Xie; Jia Lin; Teng Lei; Zhenni Lin; Christopher S. Kley; Jianmei Huang; Eran Rabani; Peidong Yang
• Keywords: Passivation

Surface condition plays an important role in the optical performance of semiconductor materials. As new types semiconductors, emerging metal-halide perovskites are promising for next-generation optoelectronic devices. We discover significantly improved light-emission efficiencies lead halide due to surface oxygen passivation. The enhancement manifests close 3 orders magnitude as perovskite dimensions decrease nanoscale, improving external quantum from <0.02% over 12%. Along with about a 4-fold increase spontaneous carrier recombination lifetimes, we show that exposure enhances light emission by reducing nonradiative channel. Supported X-ray characterization and theoretical modeling, propose excess atoms on create deep-level trap states can be passivated adsorption.