title: Formation of nanostructured porous Cu-Au surfaces: the influence of cationic sites on (electro)-catalysis.
abstract: The fabrication of nanostructured bimetallic materials through electrochemical routes offers the ability to control the composition and shape of the final material that can then be effectively applied as (electro)-catalysts. In this work a clean and transitory hydrogen bubble templating method is employed to generate porous Cu-Au materials with a highly anisotropic nanostructured interior. Significantly, the co-electrodeposition of copper and gold promotes the formation of a mixed bimetallic oxide surface which does not occur at the individually electrodeposited materials. Interestingly, the surface is dominated by Au(I) oxide species incorporated within a Cu(2)O matrix which is extremely effective for the industrially important (electro)-catalytic reduction of 4-nitrophenol. It is proposed that an aurophilic type of interaction takes place between both oxidized gold and copper species which stabilizes the surface against further oxidation and facilitates the binding of 4-nitrophenol to the surface and increases the rate of reaction. An added benefit is that very low gold loadings are required typically less than 2 wt% for a significant enhancement in performance to be observed. Therefore the ability to create a partially oxidized Cu-Au surface through a facile electrochemical route that uses a clean template consisting of only hydrogen bubbles should be of benefit for many more important reactions.
authors: School of Applied Sciences, RMIT University, GPO Box 2476V, Melbourne, VIC 3001, Australia.
authors: Ilija
authors: I
authors: Najdovski
authors: P R
authors: PR
authors: Selvakannan
authors: Suresh K
authors: SK
authors: Bhargava
authors: Anthony P
authors: AP
authors: O'Mullane
mesh_terms: D002412:Cations / Q000737:chemistry; D003300:Copper / Q000737:chemistry*; D055664:Electrochemical Techniques; D006046:Gold / Q000737:chemistry*; D006859:Hydrogen / Q000737:chemistry; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods; D009596:Nitrophenols / Q000737:chemistry; D010084:Oxidation-Reduction; D016062:Porosity; D013057:Spectrum Analysis; D013499:Surface Properties
chemical_list: D002412:Cations; D009596:Nitrophenols; D006046:Gold; D003300:Copper; D006859:Hydrogen; C024836:4-nitrophenol