Structural, elastic, electronic, optical and thermoelectric properties of metal based ternary chalcopyrite semiconductor for photovoltaic application: First-principles studies

Abstract

In this article, the physical properties of XCrS2 (X = Zn, Cd, and Hg) are studied by Density Functional Theory (DFT) using Wien2K code. Stability, along with certain parameters of the crystal structures of the compounds, was evaluated based on PBE-GGA. Mechanical properties reveal that the studied compounds XCrS2 (X = Zn, Cd) are stable, and their elastic constants and Paugh’s ratio exhibit that ZnCrS2 is brittle, whereas CdCrS2 is ductile in nature. Furthermore, HgCrS2 does not satisfy the Born stability criteria. The modified Becke-Johnson (mBJ) potential was used to improve the band gap properties and results depict that the XCrS2 (X = Zn, Cd) compounds have 1.30 and 1.27 eV direct band gaps, respectively. Thermoelectric properties exhibit the highest optical conductivity with energy loss and the strongest absorption is observed for CdCrS2 in the visible region, which also has the best photovoltaic activity. The higher obsorption nature makes this material a good candidate for solar devices. The electrical and thermal conductivity increase with an increase in temperature, and ZnCrS2 has a greater ZT compared to CdCrS2.