Bimetallic-metal oxide nanoparticles of Pt-M (M: W, Mo, and V) supported on reduced graphene oxide (rGO): radiolytic synthesis and methanol oxidation electrocatalysis

Nanocatalysts of Pt and Pt-M (M: V, MO and W) supported on rGO were successfully synthesized via a simple process based on irradiation and investigated as electrocatalysts in terms of methanol oxidation in acidic medium. Morphology, purity and composition of the catalysts were analyzed by ICP, TEM, XRD, and EDX. Irradiation caused the metallic nanoparticles (from 1 to 8 nm in diameter) to be deposited on the graphene sheets without using any stabilizer and surfactant. Bimetallic nanocatalysts exhibited higher electrochemical activities of methanol oxidation comparing to monolithic Pt catalyst at ambient temperature. A considerable increase in the effective active surface area (ECSA) was observed when the tungsten was used as the second metal; this value was in the order of Pt-Mo > Pt-V > Pt for other catalysts. Finally, high catalytic activity, great durability, and stability of Pt-W offer it to be a promising electrocatalyst for development of more advanced direct alcohol fuel cells. Graphic abstract

Automated summary

Nanocatalysts of Pt and Pt-M (M: V, MO and W) supported on rGO were successfully synthesized via irradiation, showing higher electrochemical activities for methanol oxidation. Among the catalysts, Pt-W exhibited the best performance, indicating it as a promising electrocatalyst for direct alcohol fuel cells.