Impact of Fe2(MoO4)3 and ZnMoO4 on CO Tolerance of Pt/C catalysts for enhanced methanol electrooxidation efficiency

Success of Pt/C catalyst in electrooxidation of methanol is highly influenced by its ability to withstand the poisoning effects of carbonaceous species adsorbed on the catalytic surface. Covalently bonded CO molecules occlude the active sites of the catalytic surface, impeding methanol adsorption. In this study, Pt/C-based nanocomposite catalysts were synthesized incorporating Fe2(MoO4)3 and ZnMoO4 to form heterojunctions through intermittent microwave-assisted polyol method to augment the CO oxidation pathway by introducing hydroxy groups adsorbed on their surfaces. Thorough characterization of the catalysts elucidated their chemical and phase purity, bonding configurations, and oxidation states, with various electroanalytical techniques employed to probe the mechanism of activity enhancement. Furthermore, the distinctive electron density profiles of these molybdate species have been identified as potential facilitators of methanol adsorption on the platinum surface. Equimolar composition in formulating the composite catalysts yielded a fivefold increase in catalytic activity (with ZnMoO4) and a 1.5-fold increase (with Fe2(MoO4)3). This approach demonstrates promise for tailoring Pt/C catalysts to develop industrially viable CO-tolerant and highly stable electrocatalysts.