Study of metal-Co/Zn-doped CuSCN contacts for efficient hole transport in perovskite solar cells

Developing innovative ways to revolutionize perovskite solar cell (PSC) technology requires overcoming many challenges, which has motivated extensive research on this field in the last decade. Compared to Spiro-OMETAD, CuSCN, a p-type wide bandgap semiconductor, possesses higher hole mobility, more extended stability, more suitable energy levels, and a cost-competitive hole transport layer (HTL) in the PSCs. CuSCN is insoluble in most typical solvents; consequently, its processing is still under investigation, except for sulfur-based solvents, which are among the most effective and widely studied solvents. In this work, the best morphology of CuSCN layer was obtained at its 0.3 Molar concentration in Diethyl Sulfide (DES), the most excellent polar Sulfur-based solvent, and applying Acetonitrile as the co-solvent in volume ratio of 1:1.5 (DES:Acetonitrile). Moreover, choosing the proper metal as the back contact of the CuSCN to achieve a high-quality metal contact is also considered important in this study. Because of its high conductivity, which is recommended by examining the resistivity of various metal contacts, Titanium is considered as the most suitable option to be in contact with CuSCN. Furthermore, it is found that the addition of substitution additives such as Co and Zn (0.1 M) improves the uniformity, conductivity, and solubility of CuSCN.

Automated summary

This study improves the processing and electrical performance of CuSCN by using suitable solvents and co-solvents, choosing the proper back contact metal, and adding substitution additives.