Insight into the physical properties of Rb₂YCuX₆ (X = Br and I) lead-free elpasolite for high-energy applications

Abstract

This study explores the intriguing properties of lead-free Rb2YCuX6 (X=Br and I) elpasolite, a novel class of A2B'B''X6 double perovskite materials, focusing on their structural, mechanical, and optoelectronic characteristics. The stability of the cubic structures was rigorously confirmed by calculating the tolerance factor, and octahedral factor, and employing the Birch-Murnaghan equation of states. Mechanical stability was confirmed through the examination of various parameters, revealing the materials as incompressible, hard, ductile, and anisotropic double perovskites. Analyzing the electronic band structure and density of states unveiled a distinctive indirect band gap of 2.46 eV for Rb2YCuBr6 and 2.12 eV for Rb2YCuI6, from L-X symmetry points. The optical parameters of these double perovskites were computed to evaluate their use in optical devices. Notably, their minimal light scattering, refractive index ranging from approximately 1.5 to 2, and broad absorption band within the visible spectrum make them highly suitable for optoelectronic applications, emphasizing their potential role in energy conservation and high-energy scenarios.

Revealing the Structural, Elastic, Electronic, and Optical Properties of K2ScCuCl6 and K2YCuCl6: An In-Depth Exploration Using Density Functional Theory

“…One promising class of materials for solar cell applications is double perovskites. Double perovskites are compounds composed of two transition-metal cations arranged in a perovskite crystal structure. − These materials exhibit unique electronic and optical properties that can be tailored to enhance the efficiency and cost-effectiveness of solar cells . By understanding solar cells’ materials and design aspects, particularly those based on double perovskites, we aim to contribute to advancing solar cell technology, bringing us closer to achieving affordable and efficient solar energy conversion. , The conversion of solar energy into electrical energy has seen significant advancements, with the emergence of organic–inorganic perovskite materials.…”