Electrode material and modification dependent performances of lateral photodetectors based on MAPbI3 single crystal

Abstract As new-type optoelectronic materials, organometallic halide perovskites (MAPbX3, X = I, Br, Cl) is an emerging solution-processable material with excellent optoelectronic performances that can be used for photodetectors and solar cells. Here, the effects of electrode materials (Au, Ag and Cu) on MAPbI3 single crystal photodetectors are investigated. Among the three MSCPs, the one with Au electrode exhibits the lowest dark current of 0.01 μA, which indicate that the electron drift current is the dominant component of dark current in MAPbI3 single crystals. While for the 650 nm wavelength illumination, the one with Ag electrode has largest R of 24.5 A/W and highest external quantum efficiency (EQE) of 4676% due to lower electron injection energy barrier at the contact. More importantly, the C60 layer and CuPc:C60 bulk heterojunction layer were used to modify the Au electrode respectively, a large R of 174 A/W and EQE of 33,354% is obtained by C60:CuPc-MSCP and C60-MSCP exhibits the largest PDR of 15,952 and D* of 4.5 × 1013 Jones. These results suggest that lateral photodetectors based on MAPbI3 single crystal modified by heterojunction buffer layer will obtain better optical performance.