Preparation of bismuth-doped CsPbBr3 perovskite single crystals for X-ray and gamma-ray sensing applications

Abstract

Perovskite materials are potential photo-absorbers, and their solution-processed perovskite layers are widely reported in photodetection devices. However, defects in perovskites pose a serious challenge to device performance. One possible way to overcome this set-back is growing a perovskite single crystal and deploying it in photon detection devices. Herein, we report the growth of pure and Bi-doped CsPbBr₃ perovskite single-crystals and their high-energy photodetection characteristics. The Bi-doped CsPbBr₃ perovskite single-crystals exhibited good photodetection characteristics in the visible, X-ray and gamma-ray regions. Under an illumination of 470 and 530 nm, the Bi-doped CsPbBr₃ perovskite single-crystal photodetector displayed a linear response for the biasing voltage ranging from 2 V to 5 V. The device displayed a higher magnitude of photocurrent and exhibited a better ON/OFF ratio of ∼596 at λ = 470 nm and ∼24 at λ = 530 nm. The gamma ray detection properties of the Bi-doped CsPbBr₃ perovskite single crystal were studied using two different radioactive sources with varying activity levels. A characterization study using a portable X-ray device revealed an excellent response to varying tube voltages and currents. The present study reveals the versatility of the Bi-doped CsPbBr₃ perovskite single-crystals in photon detection under a wide range of illumination.