Photonic crystal enhanced gold-silver nanoclusters fluorescent sensor for Hg2+ ion

Luminescent nanoclusters (NCs) have attracted much attention because of their good photostability and low toxicity, however, the low quantum yield is still a deficiency, and many increasing efforts are being devoted to enhance the luminescence intensity of NCs. In this paper, a method of enhancing the fluorescent signal of gold-silver nanoclusters (AuAgNCs) by photonic crystals (PhCs) was proposed. The fluorescent intensity of AuAgNCs on PhCs can be enhanced 8.0-fold in comparison to the control sample without PhCs. Furthermore, a novel fluorescence sensor of AuAgNCs based on PhCs is used for the sensitive and selective detection of Hg2+ ion in the aqueous solution, the detection limit is 0.35 nM due to the PhCs enhancement effect for the fluorescence. This proposed method may not only develop a highly sensitive method for determination of Hg2+ ion, but also expand the application of AuAgNCs in ultra-trace analysis. (C) 2020 Elsevier B.V. All rights reserved.