Electro-reduction of nitrate species on Pt-based nanoparticles: Surface area effects

The electrochemical reduction of nitrate ions was carried out on Pt-based nanoparticles supported on carbon Vulcan and deposited on a glassy carbon electrode. Different materials were evaluated: synthesized Pt-10/C, Pt-Sn-y/C (y = 10, 20 wt.%) and commercial Pt-x/C-ETEK (x = 10, 20 and 40 wt.%). Cyclic voltammetry technique was used for this purpose. It was found that the catalytic activity for hydrogen evolution reaction (HER) and nitrate electro-reduction (NER) follows the order Pt-10/C > Pt-40/C-ETEK > Pt-Sn-20/C > Pt-20/C-ETEK > Pt-Sn-10/C > Pt-10/C-ETEK. The electrochemically active surface area (ECSA), charge due to nitrate electro-reduction (Q(NO3-)), and kinetic parameters were calculated in order to understand the catalytic behavior. (C) 2010 Elsevier B.V. All rights reserved.