Low-voltage and fast-response SnO2 nanotubes/perovskite heterostructure photodetector

One-dimensional metal-oxides (1D-MO) nanostructure has been regarded as one of the most promising candidates for high-performance photodetectors due to their outstanding electronic properties, low-cost and environmental stability. However, the current bottlenecks are high energy consumption and relatively low sensitivity. Here, Schottky junctions between nanotubes (NTs) and FTO were fabricated by electrospinning SnO2 NTs on FTO glass substrate, and the bias voltage of SnO2 NTs photodetectors was as low as similar to 1.76 V, which can effectively reduce energy consumption. Additionally, for improving the response and recovery speed of SnO2 NTs photodetectors, the NTs were covered with organic/inorganic hybrid perovskite. SnO2 NTs/perovskite heterostructure photodetectors exhibit fast response/recovery speed (similar to 0.075/0.04 s), and a wide optical response range (similar to 220-800 nm). At the same time, the bias voltage of heterostructure photodetectors was further reduced to 0.42 V. The outstanding performance is mainly attributed to the formation of type-II heterojunctions between SnO2 NTs and perovskite, which can facilitate the separation of photogenerated carriers, as well as Schottky junction between SnO2 NTs and FTO, which reduce the bias voltage. All the results indicate that the rational design of 1D-MO/perovskite heterostructure is a facile and efficient way to achieve high-performance photodetectors.