High-performance and flexible CsPbBr3 UV–vis photodetectors fabricated via chemical vapor deposition

Abstract

Inorganic perovskite cesium lead halide (CsPbBr3) has attracted considerable attention because of its particularly excellent optoelectronics properties and high stability in humidity environments. Here, highly crystalline CsPbBr3 films with different morphologies and grain sizes were prepared via a one-step low pressure chemical vapor deposition (CVD). The structure-activity relationship between film microstructure and photodetectors (PDs) performance are investigated. The CsPbBr3 PD prepared at ∼190 °C possess an excellent response in the UV–Vis region and exhibits a fast response time of 0.7 ms/1.0 ms. Under 405 nm laser irradiation, the PD has a high responsivity, detectivity, external quantum efficiency, and switch ratio of 3.49 A W−1, 1.50 × 1013 Jones, 1075.4%, and 3.29 × 105, respectively. More importantly, the PD maintains 93% of original photocurrent when exposed to air for 28 d, which demonstrates excellent stability. At the same time, the CsPbBr3 films prepared via CVD are not dependent on the substrate, and the PDs exhibit similar performance on glass, SiO2/Si and polyimide substrates. The photocurrent of the flexible PD is maintained at 86% of the initial device performance parameters after 1000 bending cycles. These results indicate that the CsPbBr3 perovskite films prepared via CVD have great potential for application in high-performance, stable and flexible PDs.