Development of multifunctional coatings combining anticorrosion and antibiofouling properties
Once a metal is submerged into seawater, interactions between metal, living organisms and marine environment result in biofouling and corrosion of metal components, almost at the same time.
This thesis is focused on the development of an anti-corrosion Al-Zr film providing cathodic protection for steel parts and of a TiO2 film providing photocatalytic properties. The combination of both films is performed in order to develop a novel multi-functional coating able to avoid corrosion and biofouling of marine structures.
An optimized Al-Zr (4 at.% Zr) underlayer film was deposited by magnetron sputtering, and TiO2 was added as a top layer by aerosol CVD in order to slow down the biofouling process.
Anatase TiO2 films containing microflowers physically attached to the TiO2 films presents high decomposition rate of Orange G dye. The enhanced photocatalytic performance is associated with the high effective surface associated to the TiO2 microflowers. Electrochemical tests in saline solution have revealed that Al-Zr/TiO2 bilayers provide good protection through the preferential oxidation and an increased pitting resistance.
Finally, films of Cu-Ti-O were deposited by AAMOCVD using a combination of two precursors in order to improve photocatalytic and antibiofouling properties. Marine biofouling field test, in Lorient’s Harbor in France, were carried out in order to evaluate the antifouling performance of the coatings
Date of update November 18, 2019