SCAPS simulation and design of highly efficient CuBi2O4-based thin-film solar cells (TFSCs) with hole and electron transport layers

The continued rise in global temperatures and climate change has increased the demand for renewable energy sources. Recent developments in thin-layer photovoltaic cells have improved power output, affordability, and overall efficiency, spurred by the growing demand for renewable energy sources. In this study, numerical simulations of solar cells utilizing (SCAPS-1D) were employed to examine the efficiency of a CuBi₂O₄-based thin-film solar cell (TFSC). The CuBi₂O₄ absorber layer, known for its stability and optimal bandgap, was integrated with a Cu₂O hole transport layer (HTL), CdS buffer layer, and TiO₂ electron transference layer (ETL). Numerous constraints, including layer thickness, bandgap, and carrier concentration, were augmented to enhance the photovoltaic characteristics, such as fill factor (FF), open-circuit voltage (V_oc), efficiency (η) and short-circuit current density (J_sc). The study differentiates itself with a device structure constructed from Au/Cu₂O/CuBi₂O₄/CdS/TiO₂/FTO, which has impressive characteristics such as an open-circuit voltage of 1.2 V, a short-circuit current density of 32.85 mA/cm², a fill factor of 88.42%, and an efficiency of 34.98% at lower defect density, although this efficiency exceeds the theoretical limit established by Shockley-Queisser limit for single-junction solar cells, it is essential to recognize that limit does not consider real-world constraints such as nonradiative recombination. The reported power conversion efficiency (PCE) of 32.56% was obtained under idealized simulation conditions, characterized by minimal bulk and interfacial defect densities. These findings not only affirm the promise of CuBi₂O₄ as an eco-friendly, low-cost absorber material but also underscore the importance of accounting for both intrinsic and extrinsic defect mechanisms in simulation-driven photovoltaic design.