Study of the growth mechanism of platinum layers on the Na 0.7WO 3(100) single crystal surface

Platinum supported on Na _xWO ₃ has interesting catalytic properties in the electrolytic reduction of oxygen in fuel cells. In the present work we investigated the structure of Pt layers deposited on the Na _0.7WO ₃(100) surface by thermal evaporation or sputtering. Monitoring the intensity of the substrate and adsorbate AES signal, as well as the absorbed crystal current, it has been possible to determine that platinum grows on the substrate by the Frank-Van der Merwe (or layer-by-layer) growth mechanism.