Flexible Perovskite X-Ray Detectors through Interfacial Modification with Perylene Diimide

摘要

Flexible direct X-ray detectors based on perovskites have great potentialfor X-ray imaging due to their high sensitivity, low detection limit, low-cost,and large-area fabrication. However, these detectors perform inefficiently atX-ray-to-current conversion because of inadequate functional layer thicknessand charge-carrier recombination. Here, the fabrication of an integrated,self-powered X-ray detector based on CsPbBr_3 quantum dots and a MAPbI_3photoelectric conversion layer embedded with perylene diimide moleculesis reported. In addition to optimizing crystal domain formation and chargecarrier extraction, the perylene diimide molecules also improve the electronmobility of MAPbI_3 films by twofold. The integrated perovskite-based X-raydetector has a sensitivity of 143 169 ± 848 μC Gy_(air)~(?1) cm~(?2) and a detectionlimit of 30.77 nGy s~(?1). The perylene diimide molecule at the grain boundaryof MAPbI_3 shows defect passivation and charge collection characteristics,leading to stable output over 30 bending cycles. This hybrid molecularapproach provides insight into a general method to modify device performanceusing perylene diimide-integrated detectors for X-ray imaging of 3Dobjects with curved surfaces.