A comparative study of CuO-based heterojunction solar cells optimizing material properties for high efficiency using numerical simulations

Cupric oxide (CuO) is a key p-type semiconductor in advancing third-generation solar cells. This study analyzes four heterojunction solar cells: CuO/Si, CuO/ZnO, CuO/SnO 2 , and CuO/CdS, using SCAPS simulations. Platinum (Pt) serves as the metal contact and indium tin oxide (ITO) is the substrate layer, offering higher efficiency than traditional Si substrates. The power conversion efficiency (PCE) of the Pt/CuO/CdS/ITO cell reaches an impressive 26.59%, surpassing the PCE of Pt/CuO/ZnO/ITO at 21.87%, Pt/CuO/SnO 2 /ITO at 21.20%, and Pt/CuO/n-Si at a modest 12.1%. The thickness of the CuO layer is optimally tuned within these heterojunction structures to maximize efficiency. The bandgap, electron affinity, and carrier density of CuO were varied to assess their impact on solar cell performance. This study compared three defect states (neutral, donor, and acceptor) to determine their effects on efficiency. Importantly, donor defects were found to significantly reduce the open circuit voltage (Voc) compared to neutral and acceptor defects, highlighting the critical role of defect management in optimizing CuO-based solar cells.