Temperature-dependent electronic properties of inorganic-organic hybrid halide perovskite (CH_3NH_3PbBr_3) single crystal

摘要

In this paper, the temperature-dependent electronic properties of inorganic-organic hybrid halide perovskite (CH_3NH_3PbBr_3) single crystals are investigated. The dynamic current-time measurement results at different temperatures directly demonstrate that the electrical properties of the perovskite single crystal are dependent on the work temperature. We find that the Poole-Frankel conduction mechanism fits the current-voltage curves at small bias voltage (0-1 V) under darkness, which is mainly attributed to the surface defect states. The capability of carriers de-trapping from defects varies with different work temperatures, resulting in an increased current as the temperature increases under both darkness and illumination. In addition, the different transient photocurrent responses of incident light at two wavelengths (470 nm, 550 nm) further confirm the existence of defect states on the single crystal surface.