Surface Intermediates on Metal Electrodes at High Temperature
Abstract The mechanisms widely conceived for the O2-reduction or H2-oxidation reactions in SOFC's involve intermediate O/H species adsorbed on the electrode surface. The presence of these intermediates is investigated by linear sweep voltammetry. In air at moderate temperatures (500°C) Pt in contact with YSZ is covered with adsorbed oxygen which vanishes at high temperature (1000°C). On Ni (YSZ) a specific layer of NiO is observed above the equilibrium potential while no surface species involving hydrogen can be identified at SOFC anode conditions.