First principles calculations of Sb2Se3 and SCAPS-1D simulation-guided optimization for improved photovoltaic properties in solar cells

Abstract

This study explores the potential of Antimony Selenide (Sb₂Se₃) as an absorber layer (AL) for solar cells (SCs), focusing on its optical and electronic properties for enhancing photovoltaic performance. Using SCAPS-1D simulation and density functional theory (DFT), the material’s indirect bandgap of 1.12 eV was confirmed, with photon absorption beginning above 1 eV. The reflectivity of Sb₂Se₃ is significant in the 2.5–12 eV range, and its energy loss function is minimal in the visible spectrum, which is critical for achieving high-efficiency solar cells. Additionally, the optical conductivity peaks between 2 and 12 eV, with a maximum extinction coefficient at 2 and 9 eV, further highlighting its suitability for solar applications. The study optimizes device parameters, including defect density (Nt), absorber layer thickness, acceptor (N_A) and donor (N_D) densities, and series (Rs) and shunt (Rsh) resistances. The impact of environmental factors such as working temperature (WT) and sunlight intensity on device performance was also systematically investigated to understand the efficiency of Sb₂Se₃ solar cells under real-world conditions. Copper thiocyanate (CuSCN) and tin sulphate (SnS₂) were identified as the optimal electron transfer layer (ETL) and hole transfer layer (HTL), respectively. After these optimizations, the device demonstrated a remarkable power conversion efficiency (PCE) of 28.38%, with a short-circuit current density (Jsc) of 40.32 mA/cm², an open-circuit voltage (Voc) of 0.8207 V, and a fill factor (FF) of 85.78%. These results underscore the promising potential of Sb₂Se₃ as a high-efficiency absorber material for solar cells, with significant implications for future photovoltaic device development and material optimization strategies.