Kinetic Study of Nanostructured Rhodium Electrodes Towards Hydrogen Oxidation Reaction

J.L. FERNANDEZ; M.A. MONTERO; M.R. GENNERO DE CHIALVO; A.C. CHIALVO

Queretaro

Congreso; 64th Annual Meeting of the International Society of Electrochemistry (ISE); 2013

ISE

In recent years, hydrogen oxidation reaction (hor) has gained technological interest because it is involved in the anode of PEM fuel cells. As a consequence of that, the kinetic parameters of the hor have been evaluated on several substrates, for example, massive platinum, nanostructured platinum, bimetallic Au@Pt nanoparticles and Pd. However, this reaction has not been studied on other precious metals like Rhodium. In this context, the main objective of this work is to evaluate the kinetic parameters of hor on Rh nanostructured electrodes. As all the theoretical formalism to describe the kinetic behaviour of the hor was previously derived in our group, it is possible to correlate the experimental results with the theoretical responses. The substrate employed for the rhodium deposition was glassy carbon, which was mirror polished and electrochemical characterized in acid media previous to the deposition. The rhodium deposits were prepared by sputtering from a Rh target in argon atmosphere. The Rh/GC electrodes were voltammetrically characterized in 0.5 M H2SO4 solution in a three electrode cell. The catalytic activity towards hor was evaluated in hydrogen saturated acid solution. The measurements were done in steady state conditions using a rotating disc electrode and the active area of the working electrode was determined by CO stripping in an auxiliary cell. The nanostructured electrodes were physicochemical characterized by XPS and the surface morphology of the metallic nanostructures was characterized by AFM and SEM.