Flexible Self-Powered X-Ray Detectors Based on Wide-Bandgap Metal-Halide-Perovskite Submicrometric Thin Films

The demand for flexible and wearable sensors is more and more increasing in a wide range of applications. Specifically, in the field of medical diagnostics and radiation therapy, a flexible X-ray dosimeter is extremely desirable, due to the possibility of a conformal contact between the human body and the sensing device. Here, we report on a flexible X-ray detector based on an ultrathin (500 nm) film of a wide-bandgap metal-halide-perovskite as absorbing layer, showing sensitivity values up to 375.24 μC Gy-1 cm-2 to X-rays with energy up to 40 keV, excellent linearity with the radiation dose rate (linearity coefficient 0.97), and very good operational stability under 12 h of continuous irradiation. The device, relying on a simple low-cost technology, exploits the built-in potential of a typical p-i-n architecture used in perovskite solar cells, hence it does not require a bias voltage to operate, allowing for continuous radiation monitoring with no risk of battery depletion.