Cysteine-based silver nanoparticles as dual colorimetric sensors for cations and anions†
Abstract
We report herein the synthesis of silver nanoparticles (Ag NPs), their characterization, and anion and cation sensing properties. Freshly prepared amide–triazole Ag NPs (3a–Ag NPs and 3b–Ag NPs) could detect fluoride and cations such as Hg2+ and Cd2+ in aqueous media with a color change from pink to brown. The cysteine-based Ag NPs 5b–Ag NPs showed a colorimetric response towards H2PO4−, whereas 6–Ag NPs showed a colorimetric response towards H2PO4− and HSO4− in aqueous media.