High performance planar-heterojunction perovskite solar cells using amino-based fulleropyrrolidine as the electron transporting material†
Abstract
In this contribution, we disclose the fabrication and characterization of efficient planar-heterojunction perovskite solar cells using novel amino-based fulleropyrrolidine (C60–N) as the electron transporting material (ETM). Compared to the widely spread [6,6]-phenyl-C61-butyric acid methyl ester (PCBM), we found that C60–N can both efficiently reduce the work function of the metal cathode and passivate the trap states of the perovskite surface, further resulting in improved carrier transport, photovoltaic performance and stability. Devices using C60–N as the ETM exhibit a high power conversion efficiency (PCE) of 16.6%, significantly higher than the 12.3% of PCBM based ones. In addition, we found that C60–N can also significantly enhance the film PL lifetime and decrease the surface roughness. These findings provide insight into the selection and design of new ETMs with desirable properties.