Dual-site Hydrogen Bonding in 3D Hybrid Halide Perovskitoid Towards Stable and Sensitive Ultraviolet Light Detection

Abstract

Three-dimensional (3D) organic-inorganic hybrid perovskites (OIHPs) are known for excellent charge transport and large light absorption coefficients, making them promising materials for ultraviolet (UV) photodetection. However, the traditional 3D ABX3 perovskite structure is constrained by the tolerance factor, limiting its capacity to accommodate larger A-site cations.Therefore, it is necessary to explore novel 3D perovskitoids that can incorporate larger organic cations for UV photodetection.Herein, we introduced the diamine 3-methylaminopropylamine (3-MAPA) cation into the lead-iodide framework and successfully synthesized a 3D perovskitoid compound (3-MAPA)Pb2I6 (MPI). By forming extensive network of hydrogen bonds between the 3-MAPA 2+ cations and the inorganic framework, MPI effectively suppresses ion migration, thereby achieving ultralow dark-current drift of 8.184 × 10 -8 nA cm -1 s -1 V -1 . Owing to its 3D inorganic lattice, MPI exhibits high carrier mobility-lifetime product (μτ) of 2.613 × 10 -3 cm 2 V -1 s -1 . These synergistic effects of extensive hydrogen bonding and 3D leadhalide framework collectively enable stable UV photodetection under periodic 377 nm illumination with high responsivity (R ≈ 464.42 mA W -1) and detectivity (D * ≈ 4.05 × 10 12 Jones). This work establishes stable UV photodetection via 3D perovskitoid compound, expanding the candidate materials.