Antifouling behavior of titania–silica-reduced graphene oxide nanocomposites as coatings for marine applications

Abstract

Fouling, the unwanted accumulation of marine organisms and debris on submerged surfaces, is a pervasive problem in marine environments as it can have significant economic, environmental, and ecological consequences impacting marine industries. The present work offers a facile, low cost and eco-friendly method for developing antifouling coatings suitable for marine applications. A novel coating formulation based on reduced graphene oxide incorporated titania–silica nanocomposite (TS-RGO) was synthesized successfully using a sol–gel method. The structural, morphological, and functional features of the synthesized nanocomposites were evaluated using different characterization studies such as X-ray diffraction analysis, UV-visible spectral analysis, Fourier transform infrared spectral analysis, Raman analysis, BET surface area analysis, and scanning electron microscopy analysis. The functional nanocomposites were made into coatings of different compositions and their antifouling properties against E. coli, marine bacteria, marine algae, and freshwater algae were investigated in detail. Antifouling studies performed with freshwater and marine organisms show that the developed TS-RGO nanocomposite and its coating possess good antifouling properties. It was observed that the algal/bacterial colonies on the TS-RGO coated substrates were significantly less numerous than those on the uncoated substrates from the field experiments conducted at the Beypore Port, Calicut, Kerala. Swelling and degradation studies performed on the nanocomposite coatings in the presence of artificial seawater revealed the stability and durability of the functional coatings. Thus, the results obtained in the present work indicated the suitability of the synthesized graphene oxide incorporated titania–silica nanocomposites as antifouling agents for marine applications.