Electrodes titanium, catalyst-coated, oxygen

C. Catalyst-Coated Titanium Electrodes for Oxygen Evolution from Acid Solutions... 

As stated in the introduction, Ta coating may be used as substrate in the preparation of DSA oxygen electrodes it consists of a thin and porous layer of Iridium oxide, which acts as catalyst, obtained by thermal oxidation of an iridium compound on a valve metal. The lifetime of the anode in water electrolysis in extreme conditions of polarization (anodic current = 50 A/m ), acid concentration (30% m/m) and temperature (T = 80°C) is sensitive to the corrosion resistance of the valve metal This is shown on table I [24], which standardized life time (lifetime reported for the mass surface density of the catalyst Ir02) for some varieties of titanium base alloys and a tantalum coating as substrate ... 

Electrochemical oxidation of organic conpounds requires an anode that is stable under anodic polarization, and that hs a low catalytic efficiency for oxygen evolution. Noble metals, such as platinum, are resistant to oxidation, but they have hi catalytic efficiencies for oxygen evolution and are prone to fouling (d, 7). Dimensionally stable anodes, such as titanium coated widi active or inactive catalysts, are less prone to oxygen evolution and fouling, but ftiey do suffer from leaching of the catalyst from e electrode surface. 

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