Novel Formation of Ag/Au Bimetallic Nanoparticles by Physical Mixture of Monometallic Nanoparticles in Dispersions and Their Application to Catalysts for Aerobic Glucose Oxidation

Citations Over TimeTop 10% of 2013 papers

Abstract

Ag/Au bimetallic nanoparticles (BNPs) with a size less than 2 nm were prepared by physical mixture of colloidal dispersions of Ag and Au nanoparticles (NPs). This provides an example of fabrication of BNPs with self-organization by the reaction between metal NPs. Although Ag/Au BNPs having different structures and compositions are one of the most widely studied bimetallic systems in the literature due to their wide range of uses such as in catalysis, electronics, plasmonics, optical sensing, and surface-enhanced Raman scattering, we first prepared such BNPs by physical mixture and characterized them by UV–vis spectroscopy, SERS, XPS, TEM, and EDS in HR-STEM. The present fabrication method has the advantage of avoiding the unfavorable formation of AgCl precipitates in the reaction process which are always produced when Ag+ ions are used as a starting material in combination with a HAuCl4 precursor. These Ag/Au BNPs showed high catalytic activities for aerobic glucose oxidation, and the highest activity of 11 510 mol of glucose·h–1·mol of metal–1 was observed for the BNPs with a Ag/Au atomic ratio of 1/4; the activity value is about 2 times higher than that of Au NPs with nearly the same particle size. XPS and DFT calculation results show that the negatively charged Au atoms due to the electron charge transfer effects from neighboring Ag atoms and poly(N-vinyl-2-pyrrolidone) act as catalytically active sites and play an important role in the aerobic glucose oxidation.

Related Papers

• → Bimetallic Sites for Catalysis: From Binuclear Metal Sites to Bimetallic Nanoclusters and Nanoparticles(2023)549 cited
• → Defects engineering of bimetallic Ni-based catalysts for electrochemical energy conversion(2020)60 cited
• → Chemical Preparation of Supported Bimetallic Catalysts. Gold-Based Bimetallic, a Case Study(2016)46 cited
• → A new type of catalysts: catalysts of singly dispersed bimetallic sites(2023)12 cited
• → Nanoscale bimetallic catalysts: are they really bimetallic?(2002)4 cited