All-inorganic Perovskite CsPbBr3 Microstructures Growth via Chemical Vapor Deposition for High-Performance Photodetectors
Perovskite cesium lead halide (CsPbBr3) has attracted a considerable attention due to its excellent optoelectronic properties and superior stability against moisture, oxygen, light, and heat. In this work, the micro-environment controlled chemical vapor deposition (CVD) method has been adopted to synthesize high-quality single-crystalline CsPbBr3 microstructures, including microwires, microplates and triangular pyramids. Moreover, the structure-activity relation between the material microstructures and the device properties are illustrated. The results show that photodetectors based on single horizontal CsPbBr3 microwire exhibit a high responsivity (312.2 A W-1) and a fast response time of 5.8 ms. Photodetectors based on a single CsPbBr3 microplate exhibit a responsivity of 1.74 A W-1 and a response of 10 ms. These results indicate that the CsPbBr3 microwire photodetector is characterized by a higher photodetector performance when compared to the microplate, due to its excellent crystallization quality and the Fabry-Pérot cavity effect in the microwire. Furthermore, the flexible CsPbBr3 microwire photodetector was demonstrated on mica substrate. The results show that the photocurrent can be maintained at 90% after 3000 cycles at a bending radius of 2.5 mm. This work demonstrates the structure-activity photodetector performance, which is essential to develop a full understanding about high-performance optoelectronic devices based on all-inorganic lead halide perovskite materials.