A new AgTe_0.08S_1.67 QDs-based fluorescence sensing platform for rapidly detect UO₂²⁺ in water environment

Uranium is a vital element in energy and military applications but poses significant environmental and health risks due to its toxicity, radioactivity, and long half-life. During its use, uranium waste is released into the environment, often in the form of uranyl ions (UO₂²⁺)-the most stable and water-soluble uranium species. These ions can contaminate water sources, threatening both ecosystem safety and human health. Thus, developing rapid and sensitive methods for detecting UO₂²⁺ in aquatic environments is crucial for ensuring water security and public health.

In this study, water-phase tellurium-doped silver sulfide quantum dots (AgTe_0.08S_1.67 QDs) were synthesized using a simple and rapid one-pot method. It exhibits monodisperse spherical morphology, with a uniform average particle size of 1.92 nm. Additionally, Te doping significantly improved the fluorescence performance of this material. UO₂²⁺ can quickly quench the fluorescence of AgTe_0.08S_1.67 QDs, with a quench time as low as 1 min. The quenching mechanism is primarily attributed to the synergistic effects of electrostatic interaction and electron transfer. Meanwhile, Te doping provided binding sites and increased the electron transfer efficiency from the O and N atoms of AgTe_0.08S_1.67 QDs to the UO₂²⁺. Using this QDs as a fluorescent probe to detect UO₂²⁺, the detection limit was 3.65 nM, which is better than most fluorescent probes reported in the literature.

A new fluorescence sensor based on AgTe_0.08S_1.67 QDs was successfully developed and used to rapidly detect UO₂²⁺ with high sensitivity. This method was also successfully applied to detect UO₂²⁺ in lake water, river water and seawater, offering a new approach for the rapid detection of uranium pollutants in environmental water.