Radiation‐Induced Photovoltaic Effect in Multilayer Dion–Jacobson Hybrid Perovskite Ferroelectric Toward High‐Performance Self‐Driven X‐Ray Detection

Abstract Multilayered hybrid perovskite ferroelectrics (MHPF) have demonstrated remarkable potential for self‐driven X‐ray detection owing to their intrinsic spontaneous polarization, high absorption coefficient, and superior semiconducting properties. However, recent studies on self‐driven X‐ray detectors have mainly focused on Ruddlesden–Popper (RP) type perovskites, while the Dion–Jacobson (DJ) type MHPF, featuring strong hydrogen‐bond interactions, remain largely unexplored for X‐ray detection applications. In this work, the first realization of efficient and stable self‐driven X‐ray detection is reported in a 2D DJ‐type MHPF. Specifically, the 2D DJ perovskite (BDA)(EA) 2 Pb 3 Br 10 ( 1 , where BDA = 1,4‐butanediammonium and EA = ethylammonium) exhibits a radiation‐induced photovoltaic effect (1.14 V), which serves as the driving force for bias‐free X‐ray detection, achieving a high sensitivity of 238 µC Gy −1 cm −2 and an ultralow detection limit of 38.2 nGy s −1 . Crucially, the strong hydrogen‐bonding interactions in the DJ‐type structure contribute to a low dark current drift (1.75 × 10 −8 nA cm −1 s −1 V −1 at −100 V) and exceptional operational stability. This study not only establishes 2D DJ‐type perovskite ferroelectrics as a promising candidate for high‐performance X‐ray detection but also provides new insights into the design of next‐generation radiation detectors.