Photocatalystic Cathodic Protection of TiO2 Coating on AZ31 Magnesium Alloy
Nano TiO2 and S, N co-doped TiO2 composite coatings with WO3 transitional layer were deposited on AZ31 magnesium alloy by sol-gel method. The morphologies, structure, mechanical properties, compositional depth profiles and anti-corrosion performance of the as prepared coatings were characterized by scanning electron microscope, X-ray diffraction, nanoscratch test, glowing discharge optical emission spectrometry and electrochemical method, respectively. The results show that the nano TiO2 coatings are continuous, uniform and dense with thickness ca.3-5μm, elements in the interface diffuse mutually during heat treatment; S-N co-doped TiO2 enhances the interface adhesion, WO3 transitional layer increases the total coating thickness and strengthens the adhesion to substrate with respect to unitary TiO2 coating; S, N co-doped TiO2 acts as visible light photocatalyst that can provide permanent cathodic protection for AZ31 magnesium using WO3 as electron restoring material.
Yafang Han, Fusheng Pan, Jianmao Tang, Chungen Zhou
Z. L. Wang "Photocatalystic Cathodic Protection of TiO2 Coating on AZ31 Magnesium Alloy", Materials Science Forum, Vol. 686, pp. 280-286, 2011