Biocompatible Metal-Free Perovskite Membranes for Wearable X-ray Detectors
Xinmei Liu, Qingyue Cui, Haojin Li, Shumei Wang, Qi Zhang, Wenliang Huang, Chou Liu, Weilun Cai, Telun Li, Zhou Yang, Chuang Ma, Lixia Ren, Shengzhong Liu, Kui Zhao
Abstract
Halide perovskites are emerging as promising materials for X-ray detection owing to their compatibility with flexible fabrication, cost-effective solution processing, and exceptional carrier transport behaviors. However, the challenge of removing lead from high-performing perovskites, crucial for wearable electronics, while retaining their superior performance, persists. Here, we present for the first time a highly sensitive and robust flexible X-ray detector utilizing a biocompatible, metal-free perovskite, MDABCO-NH 4 I 3 (MDABCO = methyl- N ′-diazabicyclo[2.2.2]octonium). This wearable X-ray detector, based on a MDABCO-NH 4 I 3 thick membrane, exhibits remarkable properties including a large resistivity of 1.13 × 10 11 Ω cm, a high mobility-lifetime product (μ–τ) of 1.64 × 10 –4 cm 2 V –1, and spin Seebeck effect coefficient of 1.9 nV K –1 . We achieve a high sensitivity of 6521.6 ± 700 μC Gy air –1 cm –2 and a low detection limit of 77 nGy air s –1, ranking among the highest for biocompatible X-ray detectors. Additionally, the device exhibits effective X-ray imaging at a low dose rate of 1.87 μGy air s –1, which is approximately one-third of the dose rate used in regular medical diagnostics. Crucially, both the MDABCO-NH 4 I 3 thick membrane and the device showcase excellent mechanical robustness. These attributes render the flexible MDABCO-NH 4 I 3 thick membranes highly competitive for next-generation, high-performance, wearable X-ray detection applications.