Enhanced hole extraction in green energy perovskite solar cell by CuOx/spiro-OMeTAD bilayer with improved performance

Abstract

Hole transport layer is of vital important for improving the photo-to-electron efficiency of perovskite solar cells. In this study, we investigate the performance of meso-structure perovskite solar cell applying bilayer materials for improving hole extraction ability. By simulating the performance of perovskite solar cell using wxAMPS software, CuOx is chosen to be ideal candidate of inorganic hole transport material which can moderate device property. The optimized value band offset in schematic diagram shows that photo-generated holes could be extracted from perovskite layer to spiro-OMeTAD efficiently by applying CuOx layer at the interface of perovskite/spiro-OMeTAD. Moreover, the experiment results show that Jsc of device increase to 19.5 mA/cm2, FF increase to 65.9% and total PCE reaches 12.3% by adopting CuOx/spiro-OMeTAD bilayer as hole transfer layer. Simultaneously, hysteresis decreases from 2% to 0.7% and integrated Jsc increase from 14.8 mA/cm2 to 16.03 mA/cm2. The PL results also confirm the mechanism of carrier extraction, which is consist with experimental results. It suggests that applying CuOx/spiro-OMeTAD bilayer is an efficient way to improve performance of perovskite solar cell.