Photochromic Uranyl-Based Coordination Polymer for Quantitative and On-Site Detection of UV Radiation Dose

A highly sensitive detection of ultraviolet (UV) radiation is required in a broad range of scientific research, chemical industries, and health-related applications. Traditional UV photodetectors fabricated by direct wide-band-gap inorganic semiconductors often suffer from several disadvantages such as complicated manufacturing procedures, requiring multiple operations and high-cost instruments to obtain a readout. Searching for new materials or simple strategies to develop UV dosimeters for quantitative, accurate, and on-site detection of UV radiation dose is still highly desirable. Herein, a photochromic uranyl-based coordination polymer [(UO2)(PBPCA).DMF].DMF (PBPCA = pyridine-3,5-bis(phenyl-4-carboxylate), DMF = N,N'- dimethylformamide, denoted as SXU-1) with highly radiolytic and chemical stabilities was successfully synthesized via the solvothermal method at 100 degrees C. Surprisingly, the fresh samples of SXU-1 underwent an ultra-fast UV-induced (365 nm, 2 mW) color variation from yellow to orange in less than 1 s, and then the color changed further from orange to brick red after the subsequent irradiation, inspiring us to develop a colorimetric dosimeter based on red-green-blue (RGB) parameters. The mechanism of radical-induced photochromism was intensively investigated by UV-vis absorption spectra, EPR analysis, and SC-XRD data. Furthermore, SXU-1 was incorporated into an optoelectronic device to fabricate a novel dosimeter for convenient, quantitative, and on-site detection of UV radiation dose.

Automated summary

Highly sensitive detection of ultraviolet (UV) radiation is crucial in scientific research, chemical industries, and health-related applications. Traditional UV photodetectors have limitations in manufacturing procedures and obtaining accurate readouts. Thus, the search for new materials or simple strategies to develop UV dosimeters for quantitative, accurate, and on-site detection of UV radiation dose is highly desired. In this study, a photochromic uranyl-based coordination polymer was synthesized and a colorimetric dosimeter based on red-green-blue (RGB) parameters was developed. The mechanism of radical-induced photochromism was investigated, and the dosimeter was incorporated into an optoelectronic device for convenient, quantitative, and on-site detection of UV radiation dose.