Keggin Ions as UV-Switchable Reducing Agents in the Synthesis of Au Core−Ag Shell Nanoparticles

作者：Saikat Mandal, PR. Selvakannan, Renu Pasricha, Murali Sastry · 发表于：Journal of the American Chemical Society · 年份：2003 · DOI：10.1021/ja034972t · 被引用次数：238 · 研究领域：Nanocluster Synthesis and Applications、Advanced Nanomaterials in Catalysis、Gold and Silver Nanoparticles Synthesis and Applications

Keggin ion-mediated synthesis of Au core-Ag shell bimetallic nanoparticles is described. Exposure of photochemically reduced aqueous (PW12O40)3- Keggin ions to AuCl4- ions leads to the formation of stable gold nanoparticles capped by the Keggin ions. The surface-bound Keggin ions may then be activated by UV irradiation and, upon exposure to Ag+ ions, reduce the metal ions to form a silver shell around the gold core. That the capping agent not only stabilizes the metal nanoparticles but also plays the role of a switchable reducing agent is a highlight of this approach with important implications in nanomaterials synthesis and catalysis.