In-depth studies on the reinforced auxiliary catalysis of Mo2C in Pt-based electrocatalyst induced by metallic Fe doping for methanol electrooxidation

Abstract

Fe-doped molybdenum carbide (Mo2C) is equably and solidly loaded on the carbon nanotubes modified by amorphous carbon (CNTs@C) through combining hydrothermal reaction and carbonization process, labeling the gained composite as CNTs@C@Fe-Mo2C. Subsequently, a typical microwave-assisted polyol method is used to support Pt nanoparticles (NPs) on this composite to synthesize Pt/CNTs@C@Fe-Mo2C catalyst. Relevant structural characterization show Fe exists in the form of metal in the catalyst, and the Mo2C particles and Pt nanoparticles with small crystalline size are evenly dispersed on nanotubes. Additionally, Pt/CNTs@C@Fe-Mo2C catalyst has a commendable effect on methanol electrooxidation reaction (MOR) in acidic electrolyte (1.317 A mgPt-1), as well as in alkaline environment (3.200 A mgPt-1), moreover, its stability and anti-poisoning ability towards CO analogues have also been greatly improved. In short, these excellent results could be attributed that metallic Fe acted as an accelerant is conducive to anchoring Pt NPs and Mo2C particles onto CNTs@C, increasing the interplay between catalyst nanoparticles and support as well as reinforcing the auxiliary catalysis of Mo2C particles in Pt-based electrocatalyst, which lead the catalyst to superior catalytic activity, long-term stability and resistance for MOR, therefore, the Pt/CNTs@C@Fe-Mo2C catalyst is a right option for Pt-based electrocatalyst to inspire methanol electrooxidation.