Sintered Polycrystalline BiVO₄ Pellet for Stable X-Ray Detector with Low Detection Limit

Semiconductors based on Bi element show large attenuation coefficients to X-ray photons and have been recognized as candidates for X-ray detectors. However, the application of stable Bi-based oxide materials to X-ray detectors has been rarely investigated. In this research, the X-ray response of a BiVO4 pellet has been studied. It has been found that the BiVO4 pellet has a large resistivity of 1.3 x 10(12) omega cm, negligible current drift of 6.18 x 10(-8) nA cm(-1) s(-1) V-1 under electrical bias and mobility lifetime product, mu tau, of 1.75 x 10(-4) cm(2) V-1, which renders the pellet with an X-ray sensitivity of 241.3 mu C Gy(air)(-1) cm(-2) and a detection limit of 62 nGy(air) s(-1) under 40 KVp X-ray illumination and 40 V bias voltage. The BiVO4 pellet also shows operational stability under steady X-ray illumination with total dose of 2.01 Gy(air), equal to the dose of 20 000 medical chest X-ray inspections. This research reveals the potential application of BiVO4 in X-ray detection devices and inspires further research in this area.