Ab-initio simulations of Li-based double perovksites A2LiInBr6 (A = Rb, Cs) for solar cell applications.

[Display omitted] • Direct band gap semiconductor of Li based double perovskites halides A 2 LiInBr 6 (A = Rb, Cs) are explored in terms of density functional theory. • Structural and elastic investigation depict structural stability of A 2 LiInBr 6 in cubic phase. • The electronic band structures analysis show both materials are strong candidate for the fabrication of solar cell devices. • Optical parameters were calculated for the assurance of semiconductor behaviour. • Calculated thermoelectric parameters indicate that the both materials can be used even at elevated temperatures. We exhibit the investigation of structural, optical, thermoelectric, and electronic properties of A 2 LiInBr 6 (A = Rb, Cs) by applying density functional theory. The calculated bandgap of cubics structure using modified Becke and Johnson (mBJ) potential indicates that the bandgap reduces by replacing cations Rb to Cs. The calculated values appear in the visible energy range. Further, investigation of optical characteristics suggest that they might be used in solar cells. In addition, promising thermoelectric applications demand the small bandgap, which results from a high figure of merit for A 2 LiInBr 6. The computed small bandgap, high optical absorption, and maximum values of the figure of merit (ZT) stipulate Cs 2 LiInBr 6 applicable for solar absorbing cells and energy conversion applications. [ABSTRACT FROM AUTHOR]