Electronic Interaction between Pt and Y2O3 in Pt-Y2O3/C for Enhanced Electrocatalytic Methanol Oxidation.

Rare-earth (RE) elements are often employed to optimize electrocatalytic performance due to their tunable electronic structures and surface properties. Herein, a yttrium oxide-doped Pt-based catalyst (Pt-Y2O3/C) is engineered for the electrocatalytic methanol oxidation reaction (MOR), and the surface Y/Pt atomic ratio is precisely modulated to optimize its performance. Pt-Y2O3/C-2 (1/0.17 Pt/Y atomic ratio, Pt loading of 4.73 wt %) exhibits optimal mass activity (MA) for MOR, 5.10 A mgPt-1 in 1.0 M KOH with 1.0 M CH3OH, obviously outperforming commercial 20 wt % Pt/C by a factor of ∼12.8. It also shows superior CO-poisoning tolerance and stability; its MA for the MOR remains at 3.80 A mgPt-1 after the 10 000 s stability test. Integrated characterization results demonstrate that Y2O3 doping induces an electronic interaction with Pt, thereby reducing the electron density of Pt and optimizing its electronic structure, attenuating the adsorption of CO* intermediates at the Pt sites. Y2O3 doping also decreased the charge transfer resistance (Rct) in the MOR. The superior MOR performance of the Pt-Y2O3/C-2 catalyst originates from its uniformly sized Pt-Y2O3 nanoparticles and unique electronic effect. This work highlights the regulatory role of the rare-earth metal in Pt-based catalysts for the MOR, offering a general strategy for achieving excellent catalytic performance.