Improving efficiency of polymer hole transport layer based perovskite solar cells via interfacial modification

In triple cation perovskite solar cells (PSCs), polymer hole transport layers (HTLs) based cells usually obtained lower power conversion efficiency (PCE) than 2,2',7,7'-tetrakis (N, N-di-p-methoxyphenylamine) 9,9'-spirobifluorene (spiro-OMeTAD) HTLs based cells. In this work, perylene with excellent stability was used to modify the interface between perovskite and HTLs of poly(3-hexylthiophene) (P3HT). Our study proved that the insertion of perylene smoothed surface morphology of perovskite, decreased the trap density, assisted the charge extraction, and polished the interfacial contact. Improved photovoltaic performance and prolonged long-term stability were observed in perylene based cells. A champion PCE of 15.87 % was obtained in Perylene(3000) based cell, which was > 14 % higher than the PCE of 13.71 % obtained in reference cell. Meanwhile, the PSCs with perylene displayed better reproducibility than the reference cell. This study showed the potential of perylene like materials in efficient and stabile PSCs.