Unveiling the potential of CuAl_xGa_1−xSe₂ (x = 0.25) chalcopyrite as absorbent for photovoltaic application: first-principles insights into the structural, elastic, mechanical, electronic, thermodynamic and optical properties

Abstract

This study explores the structural, elastic, mechanical, electronic, and optical properties of CuAlxGa1−xSe2 (x = 0.25) chalcopyrite, a crucial material in photovoltaic cells. Utilizing type II-IV-V2 chalcopyrite, widely employed in high-efficiency solar cell production, we employ first-principles calculations with Tran–Blaha-modified Becke–Johnson exchange potential techniques. We aim to determine the band gap and optical properties to understand the compound’s morphology, crucial for solar cell development. Results show CuAlxGa1−xSe2 as a 1.36 eV direct band gap semiconductor. Optical characteristics, including dielectric tensor components and absorption coefficient, are calculated to assess its suitability for solar cell applications. Predictions of Young’s modulus E, Poisson’s ratio ν, bulk B, and shear G moduli provide insight into the crystal’s mechanical behavior. Additionally, phonon, dynamical stability, and thermodynamic properties are discussed, shedding light on the material’s potential in photovoltaic technology.