Air-Stable and Flexible Photodiode for X-Rays Detection Based on a Hybrid Perovskite Active Layer and Organic Interlayers

Solution-processed organic and hybrid semiconductor materials have great potential for ionizing radiation direct detection, as they combine high sensitivity, low-power consumption, and flexibility. There is, however, an open challenge related to the stability in ambient/operational conditions of this class of devices. In this work, an air-stable, solution-processed and flexible X-ray detector is reported, based on the integration of hybrid perovskite and organic thin films used as active layer and functional interlayers, respectively. The diode architecture and the engineering of the interface between the hybrid perovskite and the organic hole transporting material (solvent-modified poly(3,4-ethylenedioxythiophene):polystyrene sulfonate) is the key to achieve enhanced detector's air stability and performance. The unencapsulated flexible device, measured in air and in passive operation (0 V), shows a limit-of-detection of 0.37 ± 0.04 µGy s⁻¹ and a sensitivity as high as 5.2 µC Gy⁻¹ cm⁻², which is retained within 25% after 42 days exposure to ambient conditions.