Core−Shell Gold Nanoparticle Assembly as Novel Electrocatalyst of CO Oxidation

Abstract

This paper reports findings of an investigation of the electrocatalytic oxidation of carbon monoxide (CO) that occurs at nanocrystal gold cores with thiolate monolayer encapsulation and within a core−shell network assembly. The core−shell and network combinations allow the manipulation of core size properties and enhance the stability of nanosized catalysts against the propensity of aggregation while being catalytically active. Using alkanedithiolate-linked thin films assembled from two different gold core sizes (2 and 5 nm), we have demonstrated that the capped nanosites are both electrochemically accessible and catalytically active to CO oxidation upon electrochemical activation. Cyclic voltammetric data are presented for assessing the electrocatalytic properties. The results have important implications for the design and tailoring of nanosized gold catalysts via manipulating core−shell chemistry.