A review of Cu₂O solar cell

Cu2O-based solar cells offer a promising solution to address future energy challenges due to their affordability, eco-friendliness, and impressive power conversion efficiency (PCE). With the development of thin film deposition technology, the maximum PCE of single-junction solar cells fabricated based on Cu2O is 9.5%. Because the spectral sensitivity overlaps between Cu2O and crystalline silicon (c-Si) is small, Cu2O thin-film solar cells can be made into tandem solar cells with Si-based solar cells to achieve higher PCE. The Cu2O-Si tandem solar cell has been delivered 24.2% PCE in 2020, a time when the PCE of stand-alone silicon solar cells was 17.6%. The purpose of this paper is to summarize the development of Cu2O-based heterojunction, homojunction. The Cu2O material properties, n and p-type doping, the role of defects and impurities in bulk of films or at the interface of the p-n-junction and n-type buffer layer on the performance of Cu2O-based heterojunction like ZnO-Cu2O, and the difficulty in decreasing the interface state and doping in Cu2O homojunction solar cells are discussed. This review discusses the Cu2O film material preparation method, the history of Cu2O based solar cells, the essential factors required to enhance the performance of various types of Cu2O-based solar cells, and the potential future research opportunities for as a top subcells in Cu2O-Si tandem solar cells.