Contribution to the study of Cu-III-VI compounds

Abstract

In this work, we investigated the structural, electronic, and optical properties of CuInSe2 CuInS2 ,and their alloy CuIn(Se₁₋ₓSₓ)2 using CASTEP, based on density functional theory (DFT) with the Generalized Gradient Approximation (GGA). These simulations enabled a detailed analysis of how compositional variations and doping levels affect the band structure, dielectric function, and optical absorption characteristics. The study was complemented by SCAPS-1D simulations, which were used to simulate solar cell models incorporating these materials at compositions x = 0 and x = 1., allowing evaluation of their photovoltaic performance. Furthermore, a hybrid solar cell structure combining CuInS₂ and CIGS layers was modeled to examine the impact and importance of hybridization in reducing recombination losses, enhancing charge separation, and improving overall cell efficiency. The combined approach revealed that optimal tuning of doping concentration and absorber thickness enhances efficiency and overall solar cell performance, making CuIn(Se₁₋ₓSₓ)2 a highly promising candidate for next-generation thin-film solar technologies.