Thorium (Th), the most abundant actinide element in the Earth's crust, is often associated with rare earth elements in rare earth ores. During the extraction and processing of these ores, thorium can be released into the environment through waste and wastewater, causing radioactive contamination. Although traditional instrumental analysis techniques offer high accuracy and sensitivity, they require complex sample preparation and costly equipment, making them unsuitable for real-time rapid detection. Therefore, there is an urgent need to develop new methods for fast and portable thorium detection.

A research team led by Professor Lin Jian from the School of Nuclear Science and Technology at the School of Energy and Power Engineering of XJTU has developed a class of lanthanide metal-organic frameworks (Ln-MOFs) with tunable fluorescent colors, which serve as fluorescent chromic sensors for Th4+ ions. These sensors enable real-time visual detection of Th4+ ions through an innovative dissolution-recrystallization mechanism. Additionally, the team designed a portable RGB (red-green-blue) colorimetric photodetection device that matches the sensor's fluorescence, significantly increasing detection efficiency.

This research was recently published in the prestigious journal Angewandte Chemie International Edition. Cui Yunyi, a first-year master's student at the School of Nuclear Science and Technology of the School of Energy and Power Engineering, is the primary author of the paper, while Professor Lin is the corresponding author.