Centimeter‐Sized Molecular Perovskite Crystal for Efficient X‐Ray Detection
Chuang Ma, Fang Chen, Xin Song, Ming Chen, Lili Gao, Peijun Wang, Jialun Wen, Zhou Yang, You‐Zhi Tang, Kui Zhao, Shengzhong Liu
Abstract
Abstract Molecular perovskites have demonstrated great potential for ferroelectrics and nonlinear optics; however, their charge transport properties for optoelectronics have rarely been explored. Here, understanding of charge transport behavior of molecular perovskite under X‐ray excitation based on centimeter‐scale TMCM‐CdCl 3 (TMCM + , trimethylchloromethyl ammonium) single crystal is demonstrated. The crystal is fabricated from an aqueous solution and exhibits a large bandgap of 5.51 eV, with the valence band maximum mainly dominated by the Cl‐p/Cd‐d states and the conduction band minimum primarily by Cd‐s/Cl‐p states. Charge mobility exceeding 40 cm 2 V −1 s −1 and mobility–lifetime (µτ) product on the order of 10 −4 cm 2 V −1 for the crystal are observed. These excellent optoelectronic properties translate to an efficient photoresponse under X‐ray excitation, with the sensitivity reaching 128.9 ± 4.64 µC Gy air −1 cm −2 [fivefold higher than that of the commercialized amorphous selenium (α‐Se)] and a low detection limit of 1.06 μC Gy air −1 s −1 (10 V bias). This work pioneers a superior metal‐based molecular perovskite single‐crystal based paradigm for optoelectronic investigation, which may lead to the discovery of a new generation of X‐ray detection and imaging materials.