Mercury ion (Hg2+)is a contaminant of strong carcinogenicity,non-biodegradability and hypertoxicity,thus it is significant to design a rapid detection method of Hg2+ to protect the human health and earth environment. In this work,a radiometric fluorescence sensor,via a single excitation wavelength and dual emission wavelength,was developed by mixing gold nanoclusters (AuNCs)and carbon quantum dots (CDs)for rapid naked-eye screening and detection of Hg2+,where the AuNCs with red fluorescence were prepared by hydrothermal synthesis method,and the CDs with blue fluorescence were prepared by microwave-assistant method with high quantum yield (85%). Based on the high-affinity metallo-philic Hg2+ -Au+ interactions,the fluorescence emission peak of AuNCs at 670 nm could be quenched significantly,while the reference fluorescence intensity of CDs at 420 nm was basically not affected by Hg2+ in AuNCs-CDs. There is a linear relationship between the ratiometric fluorescence signal (I670 / I420)of AuNCs-CDs and the concentration of Hg2+(0. 005—1 mg·L-1)with the limit of detection of 1. 5 μg·L-1 . As the concentration of Hg2+ rising,the fluorescence color of AuNCs-CDs could be distinguished by bare-eyes (from pink to blue)under UV lights. This developed method was not only anti-interferential to other metal ions,but also feasible in the detection of actual samples,such as river water,rice and cabbage,with the recovery rate of Hg2+ in the range of 84. 5%—105. 1%. Therefore,AuNCs-CDs can be used to construct an ideal ratiometric fluorescent sensor for the rapid and sensitive detection of Hg2+ to the further applications on the food safety and environmental detection. © 2023 Cailiao Daobaoshe/ Materials Review. All rights reserved.
