ISSN:
1572-8838
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
,
Electrical Engineering, Measurement and Control Technology
Notes:
Abstract The effect of coating thickness and the effect of surface treatment of the titanium base metal on the surface morphology and electrochemical properties of IrO2-Ta2O5 anodes were investigated. It was observed that for an iridium content of 0.45–1.2 mg cm−2 the service life is proportional to the iridium content in the coating. During etching of titanium in 5% HF at 25 °C a surface with macroroughness is formed, while during etching in HCl at 30, 50 and 80°C a microrough surface with visible pitting is formed. The morphology of the IrO2-Ta2O5 active layer (0.32–0.39 mg Ir cm−2) depends strongly on the pretreatment of the titanium base metal. After etching of titanium in HF, the resulting IrO2-Ta2O5 layer is adherent to the macrorough surface of the titanium base metal. After etching of titanium in HCl the resulting surface of the IrO2-Ta2O5 layer is microrough with partly filled pitting holes. The service life of IrO2-Ta2O5 coating with different roughness does not differ and has a value of 1500 ± 400 h (0.5 M H2SO4, 25 °C and j = 2 A cm−2).
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00242194
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