Daizo Takaoka

Ti/Pt/(Pt-TaOX) Electrode Fabricated by Thermal Decomposition and Si/Pt/TaOX Electrode Fabricated by Sputtering for Ozone Generation

Two types of electrodes for electrochemical generation of ozone were fabricated by thermal decomposition and sputtering. Ozone generation was observed using both the electrodes. The catalyst layer of the electrode, fabricated by thermal decomposition, functions as an insulator comprising of tantalum oxide and platinum. It had many cracks, and some of them extended up to the platinum-buffered layer. However, we have not explained the ozone generation by the current concentration in the platinum-buffered layers due to the passage of an electrolyte through the cracks alone. On the other hand, the catalyst layer of the electrode fabricated by sputtering was also an insulator comprising only of tantalum oxide; this layer was also crack free. Because of the thin catalyst layer (ca. 20 nm), electrons drifted through it thereby causing electrolysis (i.e., ozone was generated). The results show that tantalum oxide functions as a catalyst of ozone generation. Therefore, with regard to electrolysis using the electrode fabricated by thermal decomposition, ozone generation by an electrochemical reaction is possible in both the thin layer of tantalum oxide, in which cracks on the inner wall extend up to the interior of the catalyst layer, and the platinum-buffered layer.