Hydrogen-Bonded Engineered One-Dimensional Metal Halides Perovskite X-ray Detectors with Enhanced Sensitivity, Low Detection Limit, and Stable Response

Abstract

Low-dimensional metal halide perovskites (MHPs) are promising X-ray detector materials, but their practical deployment is limited by high dark current and unstable device response, largely arising from weak hydrogen bonding and poor halide-ion anchoring. Here, we introduce an inter-chain halide–organic cation synergistic strategy that strengthens hydrogen bonding while immobilizing halide ions, forming a robust multi-hydrogen-bond network that suppresses ion migration in one-dimensional (1D) MHPs. Centimeter-sized 1D (Hpp)2PbBr6 (Hpp ═ 1-(4-hydroxyphenyl)piperazine)) single crystals are synthesized via a modified powder recrystallization method. In this structure, Hpp2+ cations form short, highly linear hydrogen bonds with isolated inter-chain Br– ions. This reinforced hydrogen-bonded framework increases the ion-migration activation energy to 0.52 eV and raises the Br– vacancy formation energy. Consequently, the fabricated X-ray detector achieves a sensitivity of 13439 μC Gyair–1 cm–2 at –10 V bias, representing among the best reported 1D MHP-based X-ray detectors. The device also exhibits negligible photocurrent degradation under continuous high-dose-rate X-ray irradiation of 731.3 μGyair s–1. This work establishes a structure–interaction design strategy that connects inter-chain coupling with suppressed ion migration, offering a viable route toward stable, low-detection-limit, low-dimensional MHP X-ray detectors.