Single Crystal Perovskite/Graphene Self-Driven Photodetector with Fast Response Speed.

Recently, the combination of two-dimensional (2D) materials and perovskites has gained increasing attention in optoelectronic applications owing to their excellent optical and electrical characteristics. Here, we report a self-driven photodetector consisting of a monolayer graphene sheet and a centimeter-sized CHNHPbBr single crystal, which was prepared using an optimized wet transfer method. The photodetector exhibits a short response time of 2/30 μs by virtue of its high-quality interface, which greatly enhances electron-hole pair separation in the heterostructure under illumination. In addition, a responsivity of ~0.9 mA/W and a detectivity over 10 Jones are attained at zero bias. This work inspires new methods for preparing large-scale high-quality perovskite/2D material heterostructures, and provides a new direction for the future enhancement of perovskite optoelectronics.