Benign ferroelastic twin boundaries in halide perovskites for charge carrier transport and recombination

Authors

Xun Xiao, University of North Carolina, Chapel Hill
Wenhao Li, Brown University, Providence
Yanjun Fang, University of Nebraska-Lincoln
Ye Liu, University of Nebraska-Lincoln
Yuchuan Shao, University of North Carolina, Chapel Hill
Shuang Yang, University of Nebraska-Lincoln
Jingjing Zhao, University of Nebraska-Lincoln
Xuezeng Dai, University of North Carolina, Chapel Hill
Rashid Zia, Brown University, Providence
Jinsong Huang, University of North Carolina & University of Nebraska-LincolnFollow

ORCID IDs

http://orcid.org/0000-0002-9810-2448

http://orcid.org/0000-0002-5415-1686

http://orcid.org/0000-0002-7223-2324

http://orcid.org/0000-0002-5544-590X

http://orcid.org/0000-0002-0509-8778

Document Type

Article

Date of this Version

2020

Citation

NATURE COMMUNICATIONS | (2020)11:2215 | https://doi.org/10.1038/s41467-020-16075-1 | www.nature.com/naturecommunications

Comments

The Author(s) 2020

Abstract

Grain boundaries have been established to impact charge transport, recombination and thus the power conversion efficiency of metal halide perovskite thin film solar cells. As a special category of grain boundaries, ferroelastic twin boundaries have been recently discovered to exist in both CH3NH3PbI3 thin films and single crystals. However, their impact on the carrier transport and recombination in perovskites remains unexplored. Here, using the scanning photocurrent microscopy, we find that twin boundaries have negligible influence on the carrier transport across them. Photoluminescence (PL) imaging and the spatial-resolved PL intensity and lifetime scanning confirm the electronically benign nature of the twin boundaries, in striking contrast to regular grain boundaries which block the carrier transport and behave as the non-radiative recombination centers. Finally, the twin-boundary areas are found still easier to degrade than grain interior.