Synergistic effect of RE2O3 (RE = Sm, Eu and Gd) on Pt/mesoporous carbon catalyst for methanol electro-oxidation

This work aims at developing the synergetic catalysis of rare earth oxides, which can serve as the anchoring sites for Pt and in turn as the active sites for the methanol electro-oxidation. Ordered mesoporous carbon has been modified with RE₂O₃ (RE = Sm, Eu and Gd) and subsequently deposited with Pt nanoparticles by a microwave heating process. The catalytic activities for methanol electro-oxidation are evaluated by cyclic voltammogram, chronoamperometry and electrochemical impedance spectroscopy. Pt/C-Sm₂O₃ exhibits an improvement on dispersion and electrocatalytic performance, with the highest mass activity (145.1 mA mg⁻¹) as well as good stability. A possible mechanism is proposed for the effect of RE₂O₃ on Pt nanoparticles. The adsorbed hydroxyl species supplied by RE₂O₃ in the support are contributed to the release of Pt active sites through CO removal and therefore promote the catalytic activity spontaneously.