Nanostructured Metal/Carbon Hybrids for Electrocatalysis by Direct Carbonization of Inverse Micelle Multilayers

Abstract

A synthetic strategy for the fabrication of graphitic carbon nanomaterials containing highly dispersed arrays of metal nanoparticles is reported. This synthetic strategy involves successive deposition of inverse micelle monolayers containing a metal precursor and reduction of the latter, followed by direct carbonization of the obtained multilayer structure of inverse micelles containing metal nanoparticles. Thus, a ``direct-carbonization'' concept, in which the block copolymer simultaneously serves as soft template and as carbon source, was combined with a multilayer buildup protocol. The inner architecture of the multilayer structures consisting of carbon and metal nanoparticles was studied by X-ray reflectivity, grazing incidence small-angle X-ray scattering, and cross-sectional transmission electron microscopy imaging. The hexagonal near ordering of the metal nanoparticles in the block copolymer micelle multilayers was by and large conserved after carbonization. The resulting carbon structures containing multilayers of highly dispersed metal nanoparticles exhibit superior electrocatalytic activity in formic acid and methanol oxidation, suggesting that they are promising electrode materials for fuel cells.