Electronic and optical properties of double perovskites A2BX6 (A = Cs; B = Sn, and (X = Cl, Br, I.) using modified Becke Johonson potential study

Using the density functional theory, a first-principle approach, the structural, electronic, and optical properties of the double perovskites A2BX6 (A= Cs; B=Sn; X=Cl, Br, and I) were calculated. Calculated parameters lattice constants and band gaps agree with experimental and theoretical observations. The band gap of the A2BX6 compounds is within the optimal range for single-junction photovoltaic applications. The ideal band gap, high dielectric constants, and optimum light absorption of these perovskites make them suitable for high performance single and multi-junction perovskite solar cells