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

We herein report enhanced electrical properties of the self-powered perovskite-based photodetectors with high sensitivity and responsivity by applying surface passivation strategy using C60 (fullerene) as a surface passivating agent. The perovskite (CH3NH3PbI3) thin film passivated with the fullerene achieves 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 peorvksite 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.