Revealing structural, elastic, electronic and optical properties of potential perovskites K2CuBiX6 (X=Br, Cl) based on first-principles

• Published in: Journal of solid state chemistry Vol. 310; p. 123046
• Main Authors: Hu, De-Yuan, Zhao, Xian-Hao, Tang, Tian-Yu, Lu, Li-Min, Li, Li, Gao, Li-Ke, Tang, Yan-Lin
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.06.2022
• Subjects: Electronic structure; First-principles; K2CuBiX6; Mechanical properties; Optical properties; Mechanical properties; Electronic structure; K2CuBiX6; Optical properties; First-principles
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/j.jssc.2022.123046

The structural, elastic, electronic and optical properties of K2CuBiX6 (X ​= ​Br, Cl) are studied by the first principle calculation in this paper. Their structural and thermodynamic stabilities are guaranteed by the formation energy, binding energy and Born-Huang criterion. The results of elastic constants show that the two materials are ductile and can be applied in foldable optoelectronic devices. Besides, The calculated bandgap values are 1.03 ​eV and 1.44 ​eV for K2CuBiBr6 and K2CuBiCl6, respectively, which is just in the ideal energy gap range of semiconductors. K2CuBiX6 has very small effective mass advantageous to carrier transport. In addition, the optical properties analysis shows that K2CuBiX6 has excellent light absorption properties in ultraviolet–visible wavelength. Due to their suitable bandgaps and good light absorption, K2CuBiX6 has a promising application in solar cells and other optoelectronic devices. In this study, the perovskites K2CuBiX6 (X ​= ​Br, Cl) are proposed as functional materials in solar cells. [Display omitted] •The K2CuBiX6 (X ​= ​Br, Cl) are very suitable for photosensitive materials of solar cells.•The K2CuBiX6 can be a potential candidate for excellent light absorbing material.•The K2CuBiX6 is the structural and thermodynamic stabilities.