Fig. 1From: 4-Mercaptobenzoic acid-modified Au@Ag nanoparticle-based colorimetric Cr3+ ions detection in aqueous solutionSchematic illustration of the detection of Cr3+ ions based on the aggregation of 4-MBA-Au@Ag NPs owing to the coordination between Cr3+ ions and -COOH group of the 4-MBABack to article page