One-pot synthesis of small and uniform Au@PtCu core-alloy shell nanoparticles as an efficient electrocatalyst for direct methanol fuel cells

摘要

Metal core-shell nanostructures have been extensively studied as one of the most promising electrocatalysts to significantly reduce the loading of the expensive Pt catalyst for fuel cells but it is very challenging to fabricate such a structure to possess proper metal components while making small and uniformly distributed nanoparticles for high catalytic performance. In this work, small and uniformly distributed Au-core/PtCu alloy-shell structured nanoparticles (Au@PtCu NPs) were fabricated by a novel one-pot facile method. The as-prepared Au@PtCu/C has a much larger electrochemical active surface area (ECSA) (64.8 m(2) g(Pt)(-1)) than that of AuPtCu/C(38.5 m(2) g(Pt)(-1)), PtCu/C (31.02 m(2) g(Pt)(-1)) and commercial Pt/C (25.4 m(2) g(Pt)(-1)) catalyst. This new catalyst not only greatly reduces Pt loading but also significantly increases the catalytic activity and stability toward methanol oxidation reaction in comparison to the commercial electrocatalyst. This is mainly attributed to a synergistic effect from the small and uniform core-shell nanostructure and the unique chemical compositions of Au and PtCu alloy, thus offering a great potential for a less expensive but highly active catalyst toward direct methanol fuel cells (DMFCs). (C) 2015 Elsevier B.V. All rights reserved.