Microwave synthesis and characterization of acetate-stabilized Pt nanoparticles supported on carbon for methanol electro-oxidation

Acetate-stabilized Pt nanoparticles supported on carbon were prepared by a microwave heating polyol method, in which a small amount of sodium acetate solution was added as a stabilizing agent in the synthesis solution. The Pt/C catalysts were characterized by energy-dispersive X-ray spectroscopy (EDX), transmission electron microscopy (TEM) and X-ray diffraction (XRD). It was found that the Pt nanoparticles were small and uniform in size, and highly dispersed on XC-72 carbon supports. The mean size of the Pt particles was 5.1, 4.3, 3.5 and 2.8 nm, respectively, correspondingly for adding 0, 0.1, 0.3 and 0.5 mL of 1.0 M sodium acetate solution in 50 mL of the synthesis solution. The effects of the amount of acetate solution added on the Pt particle size and size distribution were investigated. The electrochemical measurements demonstrated that the Pt/C catalysts prepared in this way exhibited a much higher electrocatalytic activity for methanol electro-oxidation than a comparative Pt/C catalyst prepared without adding acetate.