Pt–Co alloy nanoparticles synthesized on sulfur-modified carbon nanotubes as electrocatalysts for methanol electrooxidation reaction

Several Pt–Co catalyst nanoparticles supported on sulfur-modified carbon nanotubes (CNTs) have been synthesized and used for methanol oxidation reaction (MOR) in acidic solutions. The catalysts were prepared by impregnation of the catalyst precursors on the CNTs and then alloying at 800 °C under an atmosphere of H2/Ar. The results indicated that in spite of high annealing temperature, the catalyst nanoparticles were highly distributed on the support with an average particle size of ∼3 nm and narrow size distribution. Among the catalysts, Pt3Co/CNT showed highest MOR activity. Moreover, the high temperature annealing process resulted in the formation of faceted cubo-octahedral nanocrystals with high stability in acid solutions and electrochemical environments. The results demonstrated the effectiveness of sulfur-modified CNTs as a precursor for the synthesis of catalyst nanoparticles, without the need for tedious pretreatment procedures to modify CNTs or complex equipments to achieve high dispersion of nanoparticles on the CNT support.