Platinum nanoparticles supported on cerium dioxide carbon nanofibers as efficient methanol oxidation catalysts for direct methanol fuel cell

Pt-based methanol oxidation reaction (MOR) electrocatalysts with high activity, stability, and carbon monoxide (CO) tolerance are critical for advancing direct methanol fuel cells (DMFC). Herein, a low-Pt-content electrocatalyst (Pt/CeO₂-CNF) is developed through electrospinning, high-temperature calcination, and sodium borohydride (NaBH₄) reduction, featuring highly dispersed Pt nanoparticles anchored on oxygen vacancy (Ov)-rich CeO₂ embedded within carbon nanofibers (CNF). The strong metal-support interaction (SMSI) induces Pt-O-Ce interfacial bonding, facilitating electron transfer and enhancing MOR performance. Pt/CeO₂-CNF achieves a mass activity of 5.29 A mg^-1 _Pt, 3.5 times higher than commercial Pt/C, alongside exceptional stability (92% retention after 1,000 cycles) and CO tolerance. When deployed as a DMFC anode, it delivers a peak power density of 34.72 mW cm^-2, outperforming Pt/C by 31%. Characterization results indicate that SMSI induces charge redistribution between Pt and CeO₂, which synergistically enhances the reaction kinetics of MOR with the hydroxyl groups produced by CeO₂ hydrolysis. In addition, the uniform dispersion of in-situ grown CeO₂ is ensured on CNF, and Ov acts as an anchoring point to stabilize Pt nanoparticles, improving the stability of the catalyst. This work establishes a design framework for synthesizing high-performance Pt-based DMFC electrocatalysts through controlled structural and electronic modulation strategies.