Atomic-scale insights into ion migration-induced phase transition in halide perovskites

Z Zhou Li (School of Materials Science and Engineering) R Ruirong Bai (Key Laboratory of Polar Materials and Devices (MOE), School of Information and Electronic Engineering (School of Integrated Circuits Science and Engineering), East China Normal University, Shanghai, China.) W Weiqi Gao (Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University 4 , Changsha 410082,) S Sanxia Yin (National Key Laboratory of Power Semiconductor and Integration Technology, Engineering Research Center of Advanced Semiconductor Technology and Application of Ministry of Education, College of Semiconductors (College of Integrated Circuits), Hunan University 1 , Changsha 410082,) Y Yaonan Xiong B Bowen Chen X Xin Zhang P Pan Xu J Junlei Qi J Jinhua Hong Y Yiliu Wang (Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University 4 , Changsha 410082,) Y Yu-Ning Wu (Key Laboratory of Polar Materials and Devices (MOE), School of Information and Electronic Engineering (School of Integrated Circuits Science and Engineering), East China Normal University, Shanghai, China.) C Chao Ma S Shulin Chen (Changsha Semiconductor Technology and Application Innovation Research Institute, College of Semiconductors (College of Integrated Circuits))

Abstract

Phase transitions in halide perovskites significantly influence their stability and optoelectronic properties. Revealing the dynamics of octahedral distortion and ion migration during these transitions is vital to understanding their exceptional characteristics. This study reveals the atomic-scale dynamics of phase transitions induced by ion migration in mixed halide perovskites CsPbBrCl2 using an integrated differential phase contrast scanning transmission electron microscope. Unlike pure perovskites, the orthorhombic-to-cubic transition in mixed halide perovskites involves octahedral distortions and halogen migration. This ion migration facilitates a uniform halogen distribution within the structure, correcting the initially uneven arrangement. The dynamics of octahedral distortions are also examined, with accurate changes in Pb-X bond lengths and distortion angles identified throughout the transition. This cubic phase helps suppress ion migration, as supported by first-principles calculations. These in situ observations enhance the fundamental understanding of octahedral distortions and ion migration in halide perovskites, providing valuable insights for the design of stable perovskite materials.

Article Details

Volume / Issue Vol. 127, Issue 9
Published September 01, 2025
ISSN 0003-6951
Publisher American Institute of Physics

Journal Info

Applied Physics Letters

American Institute of Physics

ISSN: 0003-6951 Physical Sciences

Authors (14)

Z

Zhou Li

School of Materials Science and Engineering

R

Ruirong Bai

Key Laboratory of Polar Materials and Devices (MOE), School of Information and Electronic Engineering (School of Integrated Circuits Science and Engineering), East China Normal University, Shanghai, China.

W

Weiqi Gao

Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University 4 , Changsha 410082,

S

Sanxia Yin

National Key Laboratory of Power Semiconductor and Integration Technology, Engineering Research Center of Advanced Semiconductor Technology and Application of Ministry of Education, College of Semiconductors (College of Integrated Circuits), Hunan University 1 , Changsha 410082,

Y

Yaonan Xiong

B

Bowen Chen

X

Xin Zhang

P

Pan Xu

J

Junlei Qi

J

Jinhua Hong

Y

Yiliu Wang

Key Laboratory for Micro-Nano Optoelectronic Devices of Ministry of Education, School of Physics and Electronics, Hunan University 4 , Changsha 410082,

Y

Yu-Ning Wu

Key Laboratory of Polar Materials and Devices (MOE), School of Information and Electronic Engineering (School of Integrated Circuits Science and Engineering), East China Normal University, Shanghai, China.

C

Chao Ma

S

Shulin Chen

Changsha Semiconductor Technology and Application Innovation Research Institute, College of Semiconductors (College of Integrated Circuits)