All‐Inorganic <100>‐Oriented 2D Perovskite with High Equivalent Atomic Number for Efficient X‐Ray Absorption and Detection
Year: 2025
Type: article
Abstract: 2D perovskites are widely recognized as promising candidates for X‐ray detection. However, most 2D perovskites are organic‐inorganic hybrids with low equivalent atomic numbers, limiting their X‐ray absorption capacity, while all‐inorganic 2D perovskites typically exhibit <110> orientation, suffering from severe structural distortion and poor carrier transport. To address these challenges, an all‐inorganic sulfur‐halide mixed perovskite, BiCuSCl 2 , is proposed featuring a 2D <100>‐oriented structure, and further enhance its performance via BiOCl heteroepitaxial passivation. The all‐inorganic composition endows BiCuSCl 2 with a high equivalent atomic number across the entire X‐ray energy range, while the <100> orientation minimizes structural distortion. Meanwhile, the epitaxial BiOCl layer effectively passivates grain boundary defects and suppresses ionic migration. As a result, the BiCuSCl 2 wafer detector achieves a significantly improved µτ product (from 1.98 × 10 −3 to 7.76 × 10 −3 cm 2 V −1 ) and high resistivity (1.12 × 10 11 Ω cm). The optimized device exhibits an ultralow dark current density (6.32 × 10 −11 A cm −2 ) and a sensitivity of 219 µC Gy −1 cm −2 under identical bias. The realized specific detectivity (ratio of sensitivity to noise current density, 3.47 × 10 12 µC Gy −1 A −1 ) is among the highest all lead‐free perovskite X‐ray detectors.
Source: Advanced Optical Materials
Authors: Yuzhu Li, Shuan Kuang, Yinsheng Xu, Mengling Xia
Institution: Wuhan University of Technology
Language: English
Subfield: Radiation
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
Awards: G2056364683, G5284262993
OpenAlex ID: W4416812291