High-Stability Flexible X-ray Detectors Based on Lead-Free Halide Perovskite Cs2TeI6 Films

Normal flat panel X-ray detectors are confined in imaging of curved surfaces and three-dimensional objects. Except that, their rigid panels provide uncomfortable user experience in medical diagnosis. Here, we report a flexible X-ray detector fabricated by the combination of a lead-free Cs2TeI6 perovskite film and a polyimide (PI) substrate. High-quality Cs2TeI6 polycrystalline films are prepared by a low-temperature electro-spraying method. The resistivity even remained at the level of 10(11) Omega.cm after 100 cycles of bending tests with a low bending radius of 10 mm. The resulting flexible Cs2TeI6 detectors exhibit better response stability than those based on rigid SnO2:F glass (FTO), which is attributed to the superior crystallization of films and the growth stress relief of flexible substrates. Furthermore, an X-ray sensitivity of 76.27 mu C.Gy(air)(-1).cm(-2) and a detection limit of 0.17 mu Gy(air).s(-1) are achieved. A series of distortion-free clear X-ray images are obtained for objects with different materials and densities. These findings provide insights into flexible X-ray detectors based on perovskite films and motivate research in wearable X-ray detectors for medical radiography and dose monitoring.

Automated summary

A flexible X-ray detector based on lead-free Cs2TeI6 perovskite film and a polyimide (PI) substrate is reported, showing superior response stability and high sensitivity. Clear X-ray images without distortion are obtained for objects with different materials and densities. The findings motivate research in wearable X-ray detectors for medical radiography and dose monitoring.