Adjustable Positive-Negative Signal in Self-Driven Photodetector based on Cubic CH3NH3PbI3 Large Single Crystal


In this study, for the first time, self-driven photodetector based on cubic CH3NH3PbI3 large single crystal (C-MAPbI3 LSC) with adjustable positive-negative signal is fabricated. The preparation of MAPbI3 large single crystal (MAPbI3 LSC) is realized by the method of growth-drop-growth (GDG). The band gap of MAPbI3 single crystals with Pm-3m (221) space group (6.134×6.134×6.134 Å, 90.00 x 90.00 x 90.00) is 1.58 eV. CH3NH3+ cation is orientation-disorder within the perovskite cubo-octahedral cavity. The photocurrent density at 803 nm of the C-MAPbI3 LSC photodetector under different bias voltages is the highest under different wavelength. The responsivities (R), response time, external quantum efficiencies (EQE) and the detectivity (D) for C-MAPbI3 LSC photodetector at 803 nm wavelength with 1 W m-2, respectively, is 508.7 µA/mW, 0.1338 ms, 79.6% and 8.64*1011 Jones. Notably, the C-MAPbI3 LSC photodetector can be self-driven under 0 V bias voltage, in particular, the positive and negative values of the photocurrent can be adjusted. The proposed mechanism of poling inducing built-in potential is explained adjustable positive-negative signal in self-driven photodetector based on cubic CH3NH3PbI3 large single crystal.


Supplementary material

20210302 Electronic Supplementary Information(1)