Exploring the Structural, Mechanical, Optical and Electronic Characteristics of Pb-free A2TlRhBr¬6 (A = Na, K) Double Perovskites for Green Energy Harvesting Devices

Abstract

Here, the structural, mechanical, optical and electronic characteristics of A₂TlRhBr₆ (A=Na, K) double perovskites have been investigated computationally using density functional theory based Wien2k simulation code for green energy harvesting applications. The crystal structures are optimized at zero kelvin temperature. The computed crystal structures of both the materials display the cubic phase with space group 225 (Fm3m). The structural stability of each sample is confirmed through tolerance factor. The computed mechanical features calculated using elastic constants demonstrate that the present samples are mechanically stable while Poisson and Pugh’s ratios show the ductile behavior of both the compounds. The calculated bandgaps are found within the visible range of light. The ductile nature and suitable bandgaps suggest the present double perovskites right candidates to engineer the flexible optoelectronic devices for harvesting the green energy from the electromagnetic spectrum of light.