D. Devilliers, É. Mahé
Nov 30, 2010
Citations
3
Influential Citations
65
Citations
Journal
Electrochimica Acta
Abstract
Titanium is a valve metal able to withstand corrosion, due to the presence of a passivating layer of titanium oxide on its surface. But, due to that more or less insulating layer, titanium cannot be used directly as an anodic material. However, modification of the surface of a Ti/TiO2 substrate may lead to the formation of new structures: Ti/TiO2/M or Ti/TiO2/OX, in which M is a metal such as platinum and OX a conducting oxide exhibiting electrocatalytic properties. These structures have interesting electrochemical properties and may be used as efficient electrode materials. In this paper, after a review of the electrochemical behaviour of these structures, we give new results concerning the selective electrodeposition of lead dioxide on Ti/TiO2 substrates and we propose an interpretation of the results taking into account the dielectric properties of the underlying TiO2. It is shown that there is a dramatic decrease of the resistance of the electrode when a PbO2 layer is electrodeposited onto a Ti/TiO2 structure. That effect allows the preparation of electrodes (low-cost DSAs) that may be used as anodes in spite of the presence of the underlying TiO2 layer, that layer being useful to avoid corrosion of the titanium substrate. At last, the effect of stabilization of the underlying TiO2 layer is discussed.