Electrochemical behavior of oxide-coated Ti electrode for trivalent chromium plating

The electrochemical behavior of IrO2-containing oxide-coated Ti electrode for trivalent Cr plating was studied by polarization curve,cyclic voltammetry and passivation curve measurements. SEM images of the electrode surface showed that some IrO2 are dispersed in needlelike crystals while others are in amorphous phases. Causes for the formation of hexavalent Cr in trivalent Cr electroplating process were analyzed. The I-type oxide-coated Ti electrode developed has high activity for oxygen evolution,with electrocatalytic activity similar to that of Ti electrode produced by a foreign company. No Cr(VI) was formed in trivalent Cr plating bath by using the electrode after continuously electrolyzing for 120 A·h.