Ternary synergistic catalyst system of Pt–Cu–Mo2C with high activity and durability for alcohol oxidation

Abstract

Efficient catalyst system of high activity and durability is urgently required to convert alcohols directly on the anode in the direct alcohol fuel cells technique. Herein, an efficient ternary catalyst system of Pt–Cu–Mo2C catalyst is compositionally optimized and mechanically probed for the oxidation of methanol and ethanol fuels. Outstanding catalytic capabilities including high catalytic activity, stability, fast kinetics and high anti-poisoning ability are found due to the strong electronic effect, ligand effect and multi-oxophilic component synergism. Cu and Mo2C play different roles in the oxophilic functionalities formation as well as the anti-poisoning effect, and the combined advantages of Mo2C and Cu in the catalyst system make this ternary system more efficient for alcohols fuel oxidation compared with the traditional binary catalysts. Specifically, the peak current density of Pt–Cu–Mo2C is 80.31 mA cm−2 for methanol oxidation with a nearly 3.5-fold enhancement compared to the state-of-the-art commercial Pt/C catalyst (23.61 mA cm−2); the highest CO-tolerance ability is demonstrated by the lowest CO-oxidation peak at 0.451 V(117 mV less than Pt/C), and as high as 74.55 and 86.81% of the initial current density are maintained, respectively, after a 1000-cycle accelerated stability test towards methanol and ethanol oxidation for fuel cell reaction.