Performance and reproducibility analysis of zinc sulfo-selenide and cuprous oxide based perovskite solar cell: A SCAPS study

Abstract

The combination of titanium dioxide (TiO2) as electron transport layer (ETL) and 2,2’,7,7’-Tetrakis [N,N-di(4-methoxyphenyl)amino]−9,9’-spirobifluorene (Spiro-OMeTAD) as hole transport layer (HTL) have been frequently used in solution-processed perovskite solar cells (PSCs). However, the high sintering temperature required during the deposition of TiO2 layer and expensive Spiro-OMeTAD are limiting its commercial applicability. In this context, the combination of zinc sulfo-selenide (ZnS0.5Se0.5) (as ETL) which can be spray coated and inexpensive cuprous oxide (Cu2O) (as HTL) can serve as an alternative. This report computationally explores and compares the utility of the combination of ZnS0.5Se0.5 and Cu2O against that of TiO2 and Spiro-OMeTAD in terms of performance and reproducibility of MAPbI3 based PSC. The performance of optimized baseline models is quantitatively compared in terms of the values of performance metrics. Also, their performance is compared with respect to variations in bulk/interfacial defect density using the electrical and impedance spectroscopy characterizations. Further, their reproducibility is compared under variable carrier mobility of absorber layer. The optimized champion and mean power conversion efficiency of ZnS0.5Se0.5/Cu2O based cell are 25.6% and 25.3% respectively with standard deviation of 0.73% which is quite impressive and realistic when compared to the existing literature. The results obtained are quantitatively explained based on correlation between the cumulative effect of transit and recombination resistances evaluated using Nyquist profiles. The report systematically addresses the importance of ETL and HTL combination towards improving the performance and reproducibility of solution-processed PSCs.