Size effects of ultrafine Pt–Ru particles on the electrocatalytic oxidation of methanol

Abstract

The specific activity, isp/A m−2 (current density per real surface area), of Cl-free well-homogenized Pt–Ru particles at 25 and 60 °C in aqueous acidic solutions has been found to decrease with a decrease in the size of the Pt–Ru alloy particles, and the mass activity, imass/A g−1 (current density per mass of catalyst metal loaded), showed the same dependency when the size of the alloy particles was < ca. 3 nm in diameter.