Composite PbO(2)-TiO(2) materials deposited from colloidal electrolyte: Electrosynthesis, and physicochemical properties

Eiectrodeposition of PbO(2) from nitrate solutions in the presence of TiO(2) nanoparticles leads to composite PbO(2)-TiO(2) films. The content of the dispersed oxide which is finally occluded into the composite PbO(2) film depends on electrodeposition conditions such as pH, the value of the electrodeposition constant current or potential, the amount of added TiO(2) and on temperature. It also depends strongly on the presence of anionic additives such as sodium dodecyl sulfate (SDS) whose adsorption decreases the positive charge on the surface of the TiO(2) particles. The photo-electrocatalytic activity of the prepared materials has been tested in the oxidation of oxalic acid and benzyl alcohol. Electrodes showed a photoresponse to illumination at lambda > 320 nm confirming literature reports on synergistic effects of illumination in electro-oxidation processes at PbO(2)-based anodes. We also established that the life service of these electrodes increases by a factor of about 3 with respect to traditional PbO(2) anodes. On the other hand, the more striking achievement in the present work with PbO(2)-TiO(2) electrodes is the enhancement of electroactivity in the dark for oxalic acid, benzyl alcohol as well as for O(2) evolution