Electrocatalytic oxidation of methanol on carbon-nanotubes/graphite electrode modified with platinum and molybdenum oxide nanoparticles

摘要

Electrochemical codeposition and electrocatalytic properties of platinum and molybdenum oxide nanoparticles (Pt-MoO_x) on carbon-nanotubes/graphite electrode for methanol oxidation were investigated. The micrograph and elemental composition of the resulting Pt-MoO_x/CNTs/graphite electrode were characterized by scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDS). The results show that the Pt-MoO_x particles with the average size of about 50 nm are highly dispersed on the CNTs surface. The Pt-MoO_x/CNTs/graphite electrode delivers excellent electrocatalytic properties for methanol oxidation. The highest mass activity(A_m) reaches 264.8 A/g at the loading mass of 159.3 μg/cm~2. This may be attributed to the small particle size and high dispersion of Pt-MoO_x catalysts deposited on the CNTs surface. The kinetic analysis from electrochemical impedance spectroscopy(EIS) reveals that the existed MoO_x phase can improve the chemisorptive and catalytic properties for methanol oxidation.