Sintered polycrystalline BiVO${}_4$ 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 BiVO${}_4$ pellet has been studied. It has been found that the BiVO${}_4$ pellet has a large resistivity of 1.3 × 10${}^{12}$ Ω cm, negligible current drift of 6.18 × 10${}^{-8}$ nA cm${}^{-1}$ s${}^{-1}$ V${}^{-1}$ under electrical bias and mobility lifetime product, µτ, of 1.75 × 10${}^{-4}$ cm${}^2$ V${}^{-1}$, which renders the pellet with an X-ray sensitivity of 241.3 µC 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 BiVO${}_4$ 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 BiVO${}_4$ in X-ray detection devices and inspires further research in this area. (© 2023 Wiley‐VCH GmbH)