Fullerene-Passivated Methylammonium Lead Iodide Perovskite Absorber for High-Performance Self-Powered Photodetectors with Ultrafast Response and Broadband Detectivity

We herein report the enhanced electrical properties of self-powered perovskite-based photodetectors with high sensitivity and responsivity by applying the surface passivation strategy using C60 (fullerene) as a surface passivating agent. The perovskite (CH3NH3PbI3) thin film passivated with fullerene achieves a highly uniform and compact surface, showing reduced leakage current and higher photon-to-current conversion capability. As a result, the improved film quality of the perovskite layer allows excellent photon-detecting properties, including high values of external quantum efficiency (>95%), responsivity (>5 A W-1), and specific detectivity (>1013 Jones) at zero bias voltage, which surpasses those of the pristine perovskite-based device. Furthermore, the passivated device showed fast rise (0.18 μs) and decay times (17 μs), demonstrating high performance and ultrafast light-detecting capability of the self-powered perovskite-based photodetectors.