Facile Synthesis of PtCu Alloy/Graphene Oxide Hybrids as Improved Electrocatalysts for Alkaline Fuel Cells.

Abstract

Morphology-controllable preparation of Pt-based nanoalloys supporting on carbonaceous materials is a potential strategy to enhance the catalytic properties for oxygen reduction reaction (ORR) and ethanol oxidation reaction (EOR); they are recognized as irreplaceable electrode reactions in proton-exchange membrane ethanol fuel cells. Herein, we exhibit a facile, one-step synthesis method to directly prepare composition-tunable PtCu alloy/graphene oxide (GO) hybrids. The structure of the as-synthesized PtCu alloy/GO hybrids has been analyzed using transmission electron microscopy, high resolution transmission electron microscopy, energy-dispersive X-ray, X-ray diffraction, inductively coupled plasma, and X-ray photoelectron spectroscopy. In the PtCu alloy/GO hybrids, the PtCu alloy nanoparticles well disperse on GO, and the size is below 5.0 nm. The catalysis for ORR and EOR of the as-synthesized PtCu/GO hybrids has been evaluated in alkaline solution. Compared to commercial Pt/C, the PtCu/GO hybrids exhibit much higher mass activity and stability. The mass activities toward ORR/EOR on Pt75.4Cu24.6/GO hybrids are 5.3/2.36 times higher than the commercial Pt/C. This study proves that the as-synthesized PtCu/GO hybrids can be used as improved catalysts for ORR and EOR in alkaline medium.