Electrocatalytic Properties of Rh/C and Pt-Rh/C Catalysts Fabricated by the Method of Electrochemical Dispersion

The Pt/C, Rh/C, and Pt-Rh/C catalytic systems with uniform distribution of metal phase over the surface of carbon support and an average size of Pt and Rh nanoparticles of 7.3 and 6.5 nm, respectively, are fabricated by the method of electrochemical dispersion of metals in the aqueous electrolytes containing Na+. It is shown that the double-layer potential E = 300 mV (RHE) is the optimal potential of CO adsorption for determining the electrochemically active surface area of Pt/C, Rh/C, and Pt-Rh/C catalysts by the method of oxidative desorption of CO. The introduction of Rh into the Pt/C catalyst enables us to increase the specific activity and reduce the potential of the onset of methanol oxidation.