Characterized Semiconductor Electrodes: I . Effect of Processing Variables on the Photoelectrochemical Properties of Single Crystal (Rutile)

Abstract

The photoelectroehemical behavior of TiO2 (ruffle) electrodes has been investigated as a function of electrode preparation. Mechanical polishing of the electrodes has been found to introduce a disturbed layer on the order of 1 /~m deep. The experimental results indicate that this layer has an increased density of recombination sites. In addition, this layer affects the reduction process by which donors are created in TiO2. Etching or annealing this layer can remove it or modify its behavior. The behavior of etched and annealed electrodes in- dicates that the absorption and/or reflection of light by TiO2 can be affected by electrode processing. The stability of TiO2 electrodes is discussed in terms of their usefulness in electrochemical studies.