Tailoring the structure, composition, optical properties and catalytic activity of Ag–Au nanoparticles by the galvanic replacement reaction

• Published in: Chemical physics letters Vol. 531; pp. 188 - 192
• Main Authors: Petri, Marcos V., Ando, Rômulo A., Camargo, Pedro H.C.
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 02.04.2012
• ISSN: 0009-2614; 1873-4448
• DOI: 10.1016/j.cplett.2012.02.039

[Display omitted] ► Synthesis of Ag–Au NPs by a galvanic replacement approach between Ag and AuCl4-. ► Nanoparticles with controlled structures, compositions and optical properties. ► Evaluation of catalytic activities as a function of composition and structure. ► Increase of up to 10.9-folds due to increased Au content and hollow interiors. This Letter reports on the synthesis of Ag–Au nanoparticles (NPs) with controlled structures and compositions via a galvanic replacement reaction between Ag NPs and AuCl4-(aq) followed by the investigation of their optical and catalytic properties. Our results showed the formation of porous walls, hollow interiors and increased Au content in the Ag–Au NPs as the volume of AuCl4-(aq) employed in the reaction was increased. These variations led to a red shift and broadening of the SPR peaks and an increase of up to 10.9-folds in the catalytic activity towards the reduction of 4-nitrophenol relative to Ag NPs.