Heterovalent-Doped Sb2S3 Glass for Large-Area Sensitive X-ray Detection and Imaging

Flat-panel X-ray detectors are indispensable in a variety of imaging applications ranging from medical radiography to industrial inspections. Current commercial detectors (α-Se/CdTe) suffer from unsatisfactory image contrast and high-dose X-ray exposure owing to the limited attenuation and charge collection. Here, we show that heterovalent-doped Sb₂S₃ glass (α-Sb₂S₃) can effectively convert X-ray photons to electrical current signals. SnI₂ doping modifies the Sb–S network and stabilizes the noncrystalline structure, enabling bulk α-Sb₂S₃ with a narrow bandgap (1.66 eV), large mobility-lifetime product (5.6 × 10^–5 cm² V^–1), and strong radiation attenuation capacity simultaneously. The α-Sb₂S₃-based detector exhibits a high sensitivity of 4397 μC Gy^1– cm^–2, a low detection limit of 66 nGy s^–1, and excellent stability. Thermally evaporated α-Sb₂S₃ on a pixelated thin film transistor (TFT) backplane enables high-resolution X-ray imaging. This is the first demonstration of Sb₂S₃-based X-ray detection and imaging, creating new possibilities for the development of amorphous semiconducting materials and devices.