The ultrathin palladium nanosheets for sensitive and visual Hg2+ detection in the food chain

• DOI: 10.1016/j.jhazmat.2021.128135
• Publication Date: 2021-12-23T15:59:23Z
• Authors: Lulu Kong; Chongchong Wang; Weijie Yang; Lin Zhou; Shaohua Wei
• Keywords: Naked eye; Mercury; Noble metal; Drug Detection; Nanomaterials

The detection of mercury, one of the ten most dangerous chemicals, is significant to provide helpful information for assessing mercury toxicity and health risks. However, it is a challenge to explore simple, sensitive, accurate, and cheap Hg2+ detection methods. Noble metal nanomaterials are used for Hg2+ detection by the colorimetric method widely. Still, the pure noble metal materials' detection limit of Hg2+ is high, and sensitivity enhancement usually requires further complex modification. Here, we use a facile one-step route to synthesize ultra-thin two-dimensional palladium nanosheets (PdNS), which have high selectivity and sensitivity for Hg2+ detection by colorimetric method with a low detection limit (0.55 ppb). The detection of Hg2+ by PdNS involves multiple mechanisms, including the formation of amalgam and PdO to improve the peroxidase-mimic activity of PdNS and PdNS motor function to increase its collision probability with the detection reactant. The PdNS can be used to detect Hg2+ in various actual samples. The detection results are highly consistent with the data obtained by the atomic fluorescence spectrometer (AFS). Then, we developed a Hg2+ detection kit, which can realize simple, sensitive, and accurate Hg2+ detection by naked eye or cellphone at a meager cost (0.3 dollars each sample).