Microwave-assisted synthesis of Pt-WC/TiO2 in ionic liquid and its application for methanol oxidation

Tungsten carbide/titanium oxide (WC/titanium dioxide (TiO2)) particles are prepared by microwave-assisted heating in conjunction with ionic liquid and the subsequent reduction-carbonization. The platinum particles are loaded on the WC/TiO2 to prepare Pt-WC/TiO2. The electrocatalytic performances of the Pt-WC/TiO2 toward methanol oxidation are evaluated by cyclic voltammetry, chronoamperometry, and the CO stripping tests. It is found that electrocatalytic activity of Pt-WC/TiO2 is enhanced by adding ionic liquid (IL) during sample preparation. The results indicate that better performance toward methanol oxidation and higher tolerance to CO are achieved with an optimal addition of 1.5 ml 1-methyl-imidazoliumtetr-afluoroborate for preparing Pt-WC/TiO2. To investigate the function of IL, the phase structure and morphology of samples at different stages during preparation are examined by X-ray diffraction and transmission electron microscopy. Ionic liquid is found to act as not only a good solvent offering the excellent microwave absorption, but also a structure-directing agent to control the morphology and structure of sample, which affect the activity of the final catalysts.