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

Dylan Lu (1767172)
Ye Zhang (132223)
Minliang Lai (1552843)
Alex Lee (4569808)
Chenlu Xie (1352556)
Jia Lin (121865)
Teng Lei (4357675)
Zhenni Lin (5818195)
Christopher S. Kley (1485970)
Jianmei Huang (5180282)
Eran Rabani (1304007)
Peidong Yang (1266450)

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Publication date

October 2018

DOI

10.1021/acs.nanolett.8b02887.s001

Publisher

American Chemical Society (ACS)

Abstract

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