Fig. 2From: 4-Mercaptobenzoic acid-modified Au@Ag nanoparticle-based colorimetric Cr3+ ions detection in aqueous solutionThe effect of 4-MBA concentration on the metal ions detection system of 4-MBA-Au@Ag NPs, including colorimetric image and UV–Vis spectrum. The concentration of metal ions was all 5 × 10–3 M, and 4-MBA concentration was 10–7, 10–6, 5 × 10–6, 10–5 M, respectivelyBack to article page