A high performance Au/CH3NH3PbI3/Cu planar-type self-powered photodetector

Abstract

Self-powered photodetectors are great potential candidates in the next generation of low energy-consumption photoelectric devices. However, the planar-type metal–semiconductor–metal (MSM) self-powered photodetectors (PDs) of perovskites still suffer from poor photodetection performance. Herein, by taking advantage of the spontaneous polarization property of the CH₃NH₃PbI₃ single crystal, which can generate an extra polarization electric field, planar-type self-powered Au/CH₃NH₃PbI₃/Cu PDs with preferable photodetection capability is reported. The resultant PDs exhibit the maximum responsivity of 0.288 A W⁻¹ in 400–840 nm under the superposed built-in electric field by spontaneous polarization and asymmetric Schottky junction. Furthermore, the maximum detectivity is 4.69 × 10¹² Jones, which is the highest record among the planar-type MSM self-powered PDs based on a perovskite. Moreover, the PDs exhibited excellent operation stability with the photocurrent of the unencapsulated photodetector remaining at 92% after 15 days in atmospheric condition.