The Role of Particle Size on Bio-Fouling Properties of Oil-impregnated Nano-porous Silica Coatings

The growth of algae, barnacles, moulds and other organisms on ship hulls, concretes, painted or coated surfaces, especially in the tropics, could be harmful and aesthetically unattractive. Control of such growths usually includes the use of coatings that may contain chemicals that can destroy these organisms, and in some cases, other lives. However, manipulation of the topography of material surfaces in the so called Slippery Liquid Infused Porous Surfaces (SLIPS) seems to be excellent safety approach of tackling bio-fouling problems. In this work, we have fabricated hydrophobic silica coatings of different particle sizes, ranging from 10 nm to 700 nm; the coatings have been impregnated with non-volatile oil (squalane) to obtain artificial rims of Nepenthes Pitcher plant. Wettability and anti-biofouling tests carried out on the fabricated coatings using water drops and algal cell media have shown that surfaces coated with the smallest nano-sized particles (10 nm) possess better stability and anti-biofouling characteristics toward algae adhesion.