Effect of Different Shapes of the Titanium Based IrO2-Ta2O5 Coatings Anode on Electrochemical Properties

The titanium substrates of IrO2-Ta2O5 coating anodes were manufactured into plate and expanded mesh, respectively. The coatings were prepared by conventionally thermal decomposition with a mixture of H2IrCl66H2O dissolved in hydrochloric acid and TaCl5 dissolved in alcohol. The microstructure and electrochemical properties of the electrodes were studied with SEM, EDX, CV and accelerated life test. Compared with plate shape anode, expanded mesh anode has a little lower electrochemical activity due to less active IrO2 crystals precipitation out on it and slender cracks. However, it has longer accelerated life time due to steady and well-distributed ingredient of the coatings and less differences of the atom ratio of Ir and Ta of bulging area and flat area.