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 Pt10/C, Pt–Sny/C (y = 10, 20 wt.%) and commercial Ptx/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 Pt10/C > Pt40/C-ETEK > Pt–Sn20/C > Pt20/C-ETEK > Pt–Sn10/C > Pt10/C-ETEK. The electrochemically active surface area (ECSA), charge due to nitrate electro-reduction (QNO3−), and kinetic parameters were calculated in order to understand the catalytic behavior.