Anomalous Photovoltaic Effect in a Chiral Alternating‐Cation Intercalation‐Type Perovskite for Efficient Self‐Driven X‐Ray Detection

Abstract Organic–inorganic hybrid perovskites (OIHPs) exhibiting intrinsic anomalous photovoltaic (APV) effects have attracted considerable attention due to their exceptional optoelectronic and photovoltaic properties. However, the ionizing radiation‐induced APV effect, a promising mechanism for self‐powered X‐ray detection, remains underexplored in OIHPs. Here, this study reports for the first time the radiation‐induced APV in 2D OIHPs for efficient self‐driven X‐ray detection. Specifically, the 2D chiral alternating cation‐intercalated perovskite ( R )‐PPA(MOPA)PbBr₄ (where PPA = 1‐phenylpropylammonium and MOPA = 3‐methoxypropylammonium) demonstrates an intrinsic radiation‐induced APV of 4 V, which facilitates the separation and transport of X‐ray‐generated carriers. Remarkably, leveraging this intrinsic APV, highly efficient X‐ray detection is achieved with a high sensitivity of 475 µC Gy⁻¹ cm⁻ 2 at zero bias, surpassing most existing self‐powered X‐ray detectors. These findings underscore the potential of radiation‐responsive APV effects in advanced self‐driven X‐ray detection and pave the way for future practical applications.