Towards a long-term stable MAPbBr3 single crystal-based photoconductor with a high on/off ratio and detectivity

Abstract

Photodetectors based on lead halide perovskites often show excellent performance but poor stability. Herein, we demonstrate a photodetector based on MAPbBr₃ single crystals passivated with an ultrathin layer of PbSO₄, which shows superior detectivity and on/off ratios compared to the control device due to the combined effect of lower surface traps, reduced recombination and low dark current. In addition, the device retained ∼56% of its initial D* with an impressive on/off ratio of ∼801 after one year compared to ∼22% of D* and an on/off ratio of ∼6 of the control device.