Self-Powered X-ray Detection and Imaging using Cs₂AgBiCl₆ Lead-Free Double Perovskite Single Crystal

Despite the high performance of lead-halide perovskite-based X-ray detectors, the toxicity and instability of lead require the development of lead-free perovskites for X-ray detection applications. Here, we demonstrate lead-free and environmentally friendly, all-inorganic millimeter-sized Cs2AgBiCl6 double perovskite single crystal (SC) for X-ray detection and imaging. The high dark resistivity (3.1 × 1010 Ω cm), high carrier mobility-lifetime product (5.36 × 10–4 cm2 V–1), and lower trap density (1.18 × 109 cm–3) in these double perovskite SCs render them a potential material for X-ray detection. The fabricated vertical structured X-ray detector exhibits a sensitivity of 325.78 μC Gy air–1 cm–2 and a limit of detection of 241 nGy s–1. Additionally, the Cs2AgBiCl6 SCs exhibit self-powered X-ray detection at zero bias with a sensitivity of 7 μC Gy air–1 cm–2. Moreover, the fabricated perovskite X-ray detector exhibits a stable and robust performance under continuous X-ray irradiation and long-term ambient storage. Further, we demonstrated the imaging capability of the Cs2AgBiCl6 X-ray detector using a metal test object and obtained a distortion-free image. Our findings demonstrate that the Cs2AgBiCl6 single crystal-based X-ray detectors have great potential as practical X-ray detectors and imaging for medical radiography.