Band Gap Engineering and Optical Response of Mixed-Halide Cs2TeX6-x'Xx″ (X', X″ = Cl, Br, I, x = 0-6) Double Perovskites.
Lead-free halide perovskites are promising candidates for sustainable energy and optoelectronic applications. In this report, we investigate the systematic halide mixing in the Cs2TeX6-x'Xx″ (X', X″ = Cl/Br, Br/I, Cl/I; x = 0-6) series, using a first-principles approach. Each series exhibits a noticeable nonmonotonic c...