Three‐Dimensional Polar Perovskites for Highly Sensitive Self‐Driven X‐Ray Detection

Abstract Three‐dimensional (3D) organic–inorganic hybrid perovskites (OIHPs) have achieved tremendous success in direct X‐ray detection due to their high absorption coefficient and excellent carrier transport. However, owing to the centrosymmetry of classic 3D structures, these reported X‐ray detectors mostly require external electrical fields to run, resulting in bulky overall circuitry, high energy consumption, and operational instability. Herein, we first report the unprecedented radiation photovoltage in 3D OIHP for efficient self‐driven X‐ray detection. Specifically, the 3D polar OIHP MhyPbBr 3 ( 1 , Mhy=methylhydrazine) shows an intrinsic radiation photovoltage (0.47 V) and large mobility‐lifetime product (1.1×10 −3 cm 2 V −1 ) under X‐ray irradiation. Strikingly, these excellent physical characteristics endow 1 with sensitive self‐driven X‐ray detection performance, showing a considerable sensitivity of 220 μC Gy −1 cm −2 , which surpasses those of most self‐driven X‐ray detectors. This work first explores highly sensitive self‐driven X‐ray detection in 3D polar OIHPs, shedding light on future practical applications.