Enhancement of methanol electrocatalytic oxidation performance driven by intrinsic defects in ordered mesoporous carbon

In this study, carbon materials with ordered mesoporous structures (OMC) were used as supports for metal palladium (Pd). Using the electrocatalytic methanol oxidation reaction as a probe reaction, a series of Pd/C catalysts supported on traditional carbon materials, such as graphene (G), carbon nanotubes (CNT), carbon black (XC-72), and activated carbon (AC), were compared. Theoretical calculation predicted the promotion effect of defective carbon carrier on the electrocatalytic oxidation of methanol. The electrocatalytic methanol oxidation performance of the Pd/OMC catalyst is significantly enhanced, with its methanol oxidation reaction (MOR) activity increasing by 1.9, 1.7, 1.5, and 1.4 times compared to Pd nanoparticles (NPs) catalysts supported on G, CNT, XC-72, and AC, respectively. Raman spectroscopy combined with X-ray photoelectron spectroscopy (XPS) results revealed that the superior electrocatalytic performance of Pd/OMC was attributed to its higher intrinsic defect density, which enhanced the electronic metal-support interaction (EMSI). This interaction facilitated electron transfer from Pd NPs to the support, and the electron-deficient Pd NPs further boosted the electrocatalytic reaction performance.