Ionizing Radiation Responsive Anomalous Photovoltage Drives Sensitive Self-Powered X-Ray Detection

The anomalous photovoltaic (APV) effect in organic-inorganic hybrid perovskites (OIHPs) has attracted massive interest for developing high-performance optoelectronic devices. However, exploring the ionizing radiation responsive APV effect remains blank, let alone its potential applications. Herein, the unprecedented APV behavior in a 1D lead-free OIHP, (4-AMP)BiI5 (ABI, 4-AMP = 4-(aminomethyl)pyridine) under X-ray irradiation is reported, exhibiting a large above-bandgap bulk photovoltage of approximate to 10 V. Such a strong APV effect is closely related to the intrinsic electric polarization in polar ABI, which acts as the driving force for X-ray-generated carriers' separation and transport, thus allowing it to be self-powered. As a result, sensitive self-powered X-ray detectors based on high-quality ABI single crystals are successfully fabricated, possessing a high sensitivity of 66.84 mu C Gy-1 cm-2, a low detection limit of 482 nGy s-1, and superior operational stability. This work first demonstrates the ionizing radiation-responsive APV effect in OIHPs, which further enables passive radiation detection. The X-ray responsive anomalous photovoltage is achieved in a 1D polar lead-free hybrid perovskite, (4-(aminomethyl)pyridine)BiI5, which further enables sensitive self-powered X-ray detection. Such a first demonstration of anomalous photovoltaic effect in organic-inorganic hybrid perovskites under ionizing radiation sheds light on future design of high-performance passive radiation detectors.image