Radiation Hardness and Defects Activity in PEA₂PbBr₄ Single Crystals

Abstract Metal halide perovskites (MHPs) are low‐temperature processable hybrid semiconductor materials with exceptional performances that are revolutionizing the field of optoelectronic devices. Despite their great potential, commercial deployment is hindered by MHPs lack of stability and durability, mainly attributed to ion migration and chemical interactions with the electrodes. To address these issues, 2D layered MHPs are investigated as possible device interlayers or active material substitutes. Here, the 2D perovskite (PEA)₂PbBr₄ is considered that is recently discussed as promising candidate for X‐ray direct detection. While the increased resilience of (PEA)₂PbBr₄ radiation detectors has already been reported, the physical mechanisms responsible for such improvement compared to 3D perovskites are not still fully understood. To unravel the charge transport process in (PEA)₂PbBr₄ crystals thought to underly the device better performance, an investigation technique is adapted previously used on highly resistive inorganic semiconductors, called photo induced current transient spectroscopy (PICTS). It is demonstrated that PICTS can reliably detect three trap states (T1, T2, and T3), and that their evolution upon X‐ray exposure can explain (PEA)₂PbBr₄ superior radiation tolerance and reduced aging effects. Overall, the results provide essential insights into the electrical characteristics of 2D perovskites and their potential application as reliable direct X‐ray detectors.