One-step electrodeposition of CuSCN/CuI nanocomposite and its hole transport-ability in inverted planar perovskite solar cells

The synthesis of CuSCN/CuI nanocomposite by single-step electrodeposition is developed. The surface morphology and film thickness are controlled by changing the electrochemical potential and deposition time. The mixed-phase formation of CuSCN/CuI is confirmed through x-ray diffraction and Raman spectral analysis. Nanopetal (NP) like morphology of CuSCN/CuI is observed in FESEM micrographs. Interestingly, the NPs density and thickness are increased with increasing the deposition potential and time. The device fabricated using CuSCN/CuI nanocomposite as a hole transport layer (HTL) which is grown for 2 min delivers the best photovoltaic performance. The maximum power conversion efficiency of 18.82% is observed for CuSCN/CuI NP with a density of 1153 μm⁻² and thickness of 142 nm. The charge transfer ability of the CuSCN/CuI NP HTL is analyzed by electrochemical impedance spectroscopy. Based on the observation, moderate charge transport resistance and optimum film thickness are required for achieving maximum photovoltaic performance in perovskite solar cells (PVSCs). Thus, the developed CuSCN/CuI NP HTL is a potential candidate for PVSCs. (paper)