Evaluation of the Catalytic Activity of Faceted Platinum Nanostructured Electrodes for Hydrogen Oxidation Reaction

M.A. MONTERO; M.R. GENNERO DE CHIALVO; A.C. CHIALVO

Praga

Congreso; 63st Annual Meeting of the International Society of Electrochemistry (ISE); 2012

International Society of Electrochemistry (ISE)

The substrate employed for the platinum deposition was glassy carbon, which was mirror polished and electrochemically characterized previous to the deposition in acid media. The platinum deposition was done following the procedure described by Tian et al and it consisted in a double potential pulse procedure. It is first applied to the electrode a nucleation pulse in order to generate metallic nucleus and the second step consisted in the application of a square wave potential to grow these nucleus. Consecutive to this, the electrode was subjected to a faceting treatment, which consisted in the application of a square wave potential in ascorbic acid solution. The dependence of the particle size and distribution with the nucleation and growth pulses potential and time was employed in order to have electrodes with different configurations. These Pt/GC electrodes were voltammetric characterized in acid media and the catalytic activity towards hydrogen oxidation reaction (hor) was evaluated in steady state conditions. All the theoretical formalism to describe the kinetic behaviour of the hor was previously derived in our group, so it was possible to compare the experimental results with the theoretical responses. The Pt nanostructures were superficially characterized by AFM and SEM.