Preliminary Evaluation of Functional Coatings for Marine Based Renewable Energy Applications

The reliability and maintenance of the tidal turbines is found to be a major problem due to cavitation erosion. The presence of hydrogen sulphide in the microbes leads to Microbially Induced Corrosion (MIC) in objects in the marine environment which can instigate biofouling to occur. Together, the synergistic effect of erosion, corrosion and fouling leads to reduced lifespan of the structural and operational components. Given the sheer scale of the marine renewable industry, which is estimated to reach around €9 billion by 2030, the effects of cavitation, corrosion and biofouling can cause large losses to the industry which will further spur significant costs in the operation of such offshore technology. This is the main driver behind developing eco-friendly multi-functional sol-gel coatings for marine renewable applications. The present research is designed to investigate the two sol-gel coatings synthesized from organically modified silicon precursor 3-methacryloxypropyltrimethoxysilane (MAPTMS) mixed with zirconium (IV) propoxide. One of the coatings was modified using 1%v/v of hexamethyl di-isocyanate (HMDI) diluted in 60% ethanol (S65) whereas the second coating left unmodified (S6) diluted in 100% ethanol. The coatings were deposited on the aluminium (Al) panel using dip coater. The structure of the coatings was evaluated using ATR-FTIR. The coating properties such as hardness, adhesion and wettability were evaluated using pencil hardness, cross-cut adhesion, and water contact angle. Subsequently, the thermal and the chemical stability of the sol-gel coatings was also evaluated.