Entropy-Driven Stabilization of Multielement Halide Double-Perovskite Alloys

Xinjiang Wang; Jingxiu Yang; Xueting Wang; Muhammad Faizan; Hongshuai Zou; Kun Zhou; Bangyu Xing; Yuhao Fu; Lijun Zhang

doi:10.1021/acs.jpclett.2c01180

Entropy-Driven Stabilization of Multielement Halide Double-Perovskite Alloys

J Phys Chem Lett. 2022 Jun 9;13(22):5017-5024. doi: 10.1021/acs.jpclett.2c01180. Epub 2022 Jun 1.

Authors

Xinjiang Wang¹, Jingxiu Yang², Xueting Wang³, Muhammad Faizan⁴, Hongshuai Zou⁴, Kun Zhou⁴, Bangyu Xing⁴, Yuhao Fu^{1

5}, Lijun Zhang^{4

5}

Affiliations

¹ State Key Laboratory of Superhard Materials, College of Physics, Jilin University, Changchun 130012, China.
² Key Laboratory for Comprehensive Energy Saving of Cold Regions Architecture of Ministry of Education, School of Materials Science and Engineering, Jilin Jianzhu University, Changchun 130118, China.
³ Shandong Provincial Key Laboratory of Optical Communication Science and Technology, and School of Physical Science and Information Engineering, Liaocheng University, Liaocheng 252059, China.
⁴ State Key Laboratory of Superhard Materials, Key Laboratory of Automobile Materials of MOE, College of Materials Science and Engineering, Jilin University, Changchun 130012, China.
⁵ International Center of Computational Method and Software, Jilin University, Changchun 130012, China.

PMID: 35649269
DOI: 10.1021/acs.jpclett.2c01180

Abstract

Currently, a major obstacle restricting the commercial application of halide perovskites is their low thermodynamic stability. Herein, inspired by the high-stability high-entropy alloys, we theoretically investigated a variety of multielement double-perovskite alloys. First-principles calculations show that the entropy contribution to Gibbs free energy, which offsets the positive enthalpy contribution by up to 35 meV/f.u., can significantly enhance the material stability of double-perovskite alloys. We found that the electronic properties of bandgaps (1.04-2.21 eV) and carrier effective masses (0.34 to greater than 2 m₀) of the multielement double-perovskite alloys can be tuned over a wide range. Meanwhile, the parity-forbidden condition of optical transitions in the Cs₂AgInCl₆ perovskite can be broken because of the lower symmetry of the configurational disorder, leading to enhanced transition intensity. This work demonstrates a promising strategy by utilizing the alloy entropic effect to further improve the material stability and optoelectronic performance of halide perovskites.