Plasma-induced synthesis of Pt nanoparticles supported on TiO2 nanotubes for enhanced methanol electro-oxidation

Abstract A Pt/C/TiO 2 nanotube composite catalyst was successfully prepared for enhanced methanol electro-oxidation. Pt nanoparticles with a particle size of 2 nm were synthesized by plasma sputtering in water, and anatase TiO 2 nanotubes with an inner diameter of approximately 100 nm were prepared by a simple two-step anodization method and annealing process. Field-emission scanning electron microscopy images indicated that the different morphologies of TiO 2 synthesized on the surface of Ti foils were dependent on the different anodization parameters. The electrochemical performance of Pt/C/TiO 2 catalysts for methanol oxidation showed that TiO 2 nanotubes were more suitable for use as Pt nanoparticle support materials than irregular TiO 2 short nanorods due to their tubular morphology and better electronic conductivity. X-ray photoelectron spectroscopy characterization showed that the binding energies of the Pt 4f of the Pt/C/TiO 2 nanotubes exhibited a slightly positive shift caused by the relatively strong interaction between Pt and the TiO 2 nanotubes, which could mitigate the poisoning of the Pt catalyst by CO ads , and further enhance the electrocatalytic performance. Thus, the as-obtained Pt/C/TiO 2 nanotubes composites may become a promising catalyst for methanol electro-oxidation.