Electro-Catalytic Oxidation of Methanol Catalyzed by Facet-Controlled Pt-WC Nanoparticles on In Situ Synthesized Carbon Nanotubes

The facet-controlled Pt-WC nanoparticles on in situ synthesized carbon nanotubes (Pt-WC/CNT) are prepared by the one-step carburization in conjunction with simple displacement reaction. WC particles exhibit preferential (100) orientation due to the in situ growth of carbon nanotubes (CNTs), and the most predominant facet exhibited by the Pt immobilized on WC (100) is the (200) facet. Among the prepared catalysts, Pt-WC/CNT-2 shows the highest mass activity (2540.0 mA/mg Pt) for methanol oxidation reaction (MOR) with smaller onset overpotential (0.18 V) and lower activation free energy (32.87 kJ/mol) in acid media. Such enhanced catalytic activity originates from its larger ECSA (238.1 m(2)/g) and the synergistic effect of facet-controlled Pt-WC nanoparticles. And Pt-WC/CNT catalyst has superior stability for MOR due to its structurally stable CNTs support, which provides a large area to contact with electrolyte, and facilitates the electron transfer.