Title: Regulating off-centering distortion maximizes photoluminescence in halide perovskites

Abstract

Metal halide perovskites possess unique atomic and electronic configurations that endow them with high defect tolerance and enable high-performance photovoltaics and optoelectronics. Perovskite light-emitting diodes have achieved an external quantum efficiency of over 20%. Despite tremendous progress, fundamental questions remain, such as how structural distortion affects the optical properties. Addressing their relationships is considerably challenging due to the scarcity of effective diagnostic tools during structural and property tuning as well as the limited tunability achievable by conventional methods. Here, using pressure and chemical methods to regulate the metal off-centering distortion, we demonstrate the giant tunability of photoluminescence (PL) in both the intensity (> 20 times) and wavelength (> 180 nm/GPa) in the highly distorted halide perovskites [CH₃NH₃GeI₃, HC(NH₂)₂GeI₃, and CsGeI₃]. Using advanced in situ high-pressure probes and first-principles calculations, we quantitatively reveal a universal relationship whereby regulating the level of off-centering distortion towards 0.2 leads to the best PL performance in the halide perovskites. By applying this principle, intense PL can still be induced by substituting CH₃NH₃⁺ with Cs⁺ to control the distortion in (CH₃NH₃)_1-xCs_xGeI₃, where the chemical substitution plays a similar role as external pressure. The compression of a fully substituted sample of CsGeI₃ further tunes the distortion to themore » optimal value at 0.7 GPa, which maximizes the emission with a 10-fold enhancement. This work not only demonstrates a quantitative relationship between structural distortion and PL property of the halide perovskites but also illustrates the use of knowledge gained from high-pressure research to achieve the desired properties by ambient methods.« less

Authors:

Lü, Xujie  ^[1];

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Stoumpos, Constantinos ^[2]; Hu, Qingyang  ^[1];

• Search DOE PAGES for author "Hu, Qingyang"
• Search DOE PAGES for ORCID "0000-0002-2742-3017"

Ma, Xuedan ^[3]; Zhang, Dongzhou ^[4]; Guo, Songhao ^[1]; Hoffman, Justin ^[5]; Bu, Kejun ^[1]; Guo, Xiaofeng ^[6]; Wang, Yingqi ^[1]; Ji, Cheng ^[1]; Chen, Haijie ^[5]; Xu, Hongwu ^[7]; Jia, Quanxi ^[8]; Yang, Wenge ^[1]; Kanatzidis, Mercouri G. ^[5]; Mao, Ho-Kwang ^[1]

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+ Show Author Affiliations

1. Center for High Pressure Science and Technology Advanced Research (HPSTAR), Shanghai 201203, China
2. Department of Chemistry, Northwestern University, Evanston, IL 60208, USA, Department of Materials Science and Technology, Voutes Campus, University of Crete, Heraklion GR-70013, Greece
3. Center for Nanoscale Materials, Argonne National Laboratory, Lemont, IL 60439, USA
4. Partnership for Extreme Crystallography, University of Hawaii at Manoa, Honolulu, HI 96822, USA
5. Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
6. Department of Chemistry and Alexandra Navrotsky Institute for Experimental Thermodynamics, Washington State University, Pullman, WA 99164, USA
7. Earth and Environmental Sciences Division, Los Alamos National Laboratory, Los Alamos, NM 87545, USA
8. Department of Materials Design and Innovation, University at Buffalo—The State University of New York, Buffalo, NY 14260, USA

Publication Date:

Mon Nov 30 00:00:00 EST 2020

Research Org.:

Univ. of California, Santa Barbara, CA (United States); Northwestern Univ., Evanston, IL (United States)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE National Nuclear Security Administration (NNSA)

OSTI Identifier:

1819801

Alternate Identifier(s):

OSTI ID: 1870320

Grant/Contract Number:  

89233218CNA000001; SC0012541; AC02–06CH11357; NA0001974; AC02-06CH11357; FG02-94ER14466; 51527801; U1930401; 17N1051-0213; EAR-1634415; EAR-1661511

Resource Type:

Published Article

Journal Name:

National Science Review

Additional Journal Information:

Journal Name: National Science Review Journal Volume: 8 Journal Issue: 9; Journal ID: ISSN 2095-5138

Publisher:

Oxford University Press

Country of Publication:

China

Language:

English

Subject:

halide perovskites; high pressure; off-centering distortion; optical properties; lone-pair electrons; quantitative relationship