The electrochemistry of nitrogen-containing compounds at platinum single crystal electrodes - Part 3. Carbohydrazide on Pt(hkl) electrodes

The electrochemical behaviour of platinum single crystal electrodes in carb ohydrazide containing solutions has been investigated by means of cyclic vo ltammetry and in situ FTIR spectroscopy. The spectroscopic and voltammetric results have shown that the main reaction path of carbohydrazide oxidation goes through formation of COads at potentials between 0.2 and 0.4 V RHE. A t potentials higher than 0.4 V, a direct oxidation path to CO2 can be propo sed. On Pt(100) and Pt(111) a second reaction path involves the cleavage of N-N bonds leading to the formation of semicarbazide and urea at potentials below 0.25 V. Formation of adsorbed urea and NO has also been detected at potentials higher than 0.5 V on these surfaces. On Pt(110), the fast format ion of adsorbed CO impedes other possible reaction pathways. (C) 1999 Elsev ier Science S.A. All rights reserved.