Electrocatalysis of oxygen reduction on carbon-supported PtCo catalysts prepared by water-in-oil micro-emulsion

Synthesis of carbon-supported PtCo/C using micro-emulsion method including simultaneous procedure and sequential procedures in both acid and alkaline media was reported. UV–vis and electron microscopy were used to characterize the formation, surface morphology and distribution of PtCo nanoparticles. Crystallite structure of catalysts was analyzed from XRD patterns. Catalytic properties of PtCo/C catalysts synthesized were compared with commercial Pt/C using RDE based on both mass activity (MA) and specific activity (SA). PtCo/C catalysts prepared in both acidic and basic conditions showed better performance than commercial Pt/C catalyst. High-temperature heat treatment was found useful only to PtCo/C by sequential procedure. The peroxide yield was also explored using RRDE technique. The H2O2 yield results were correlated with SA and R values (ratio of charge transferred about Co and Pt on the surface of catalyst) obtained from CVs in 1 M KOH solution. A sacrificial Co oxidized effect on impediment of adsorption of OH may cause higher catalytic properties and higher H2O2 yield to Pt base alloy catalysts.