Lead‐Free Halide Double Perovskites Cs2KXCl6 (X = Tl, As): A First‐Principles Study of Electronic, Optical, and Thermoelectric Properties
Halide double perovskites based on non‐toxic elements are promising materials for energy conversion and optoelectronic applications. Here, we systematically investigate the structural, mechanical, electronic, optical, and thermoelectric properties of lead‐free Cs2KXCl6 (X = Tl, As) using first‐principles calculations w...