Chemical Trends in the Thermodynamic Stability and Band Gaps of 980 Halide Double Perovskites: A High-Throughput First-Principles Study

Tao Zhang; Zenghua Cai; Shiyou Chen

doi:10.1021/acsami.0c03622

Chemical Trends in the Thermodynamic Stability and Band Gaps of 980 Halide Double Perovskites: A High-Throughput First-Principles Study

ACS Appl Mater Interfaces. 2020 May 6;12(18):20680-20690. doi: 10.1021/acsami.0c03622. Epub 2020 Apr 21.

Authors

Tao Zhang¹, Zenghua Cai^{1

2}, Shiyou Chen^{1

3}

Affiliations

¹ Key Laboratory of Polar Materials and Devices (MOE) and Department of Electronics, East China Normal University, Shanghai 200241, China.
² Department of Physics and Key Laboratory for Computational Physical Science (MOE), Fudan University, Shanghai 200433, China.
³ Collaborative Innovation Center of Extreme Optics, Shanxi University, Shanxi 030006, China.

PMID: 32281362
DOI: 10.1021/acsami.0c03622

Abstract

The chemical trends in the thermodynamic stability and band gaps of 980 A₂B⁺B³⁺X₆ halide double perovskites are revealed based on high-throughput first-principles calculations. To accurately predict the stability with respect to phase decomposition, all known metal halides in the Materials Project database are considered as the competing compounds. The energies above the convex hull show that only 112 of 980 double perovskites are stable and 27 double perovskites that had been predicted to be stable in the literature are actually unstable after considering more competing compounds. The stability of these double perovskites is determined mainly by A, X, and B⁺ elements and increases gradually as A becomes heavier (from Li to Cs) and X becomes lighter (from I to F). The band gaps are determined mainly by X, B⁺, and B³⁺ elements, decreasing monotonically as X becomes heavier while changing nonmonotonically as B⁺ and B³⁺ change. These chemical trends provide clear instructions for the design of double perovskites with good stability and suitable band gaps for various applications, i.e., through choosing heavier A cations (e.g., large organic cations), stable double perovskites can be designed with band gaps tunable in a wide range of 0-7 eV (infrared to ultraviolet); however, through choosing light X anions, stable double perovskites can be designed with only wide band gaps.

Keywords: ab initio calculations; band gap; double perovskites; high-throughput screening; thermodynamic stability.