Freshwater production via efficient oil-water separation and solar-assisted water evaporation using black titanium oxide nanoparticles

Abstract Fabrication of a multipurpose superhydrophobic mesh via modification of a galvanized steel mess using black titanium oxide nanoparticles and perfluorodecyltriethoxysilane is reported. Modified mesh exhibits superhydrophobicity with a water static contact angle of 157°±2 along with a tilt angle of 5°±1 and suitable chemical, thermal, mechanical stability, and self-cleaning ability. The droplet dynamic behavior of coated over superhydrophobic mesh revels the impact velocity is 1.5 ms-1 for splashing of the water droplet. The developed mesh is studied for freshwater generation from oily water and seawater via efficient oil-water separation and solar evaporation, respectively. A proficiency of 99% and 88% is achieved for oil-water separation from mixture and emulsion, respectively. Solar evaporation efficiency of 64% and 76% are recorded under low-intensity light (225 Wm-2) and natural sunlight (591 Wm-2), respectively, from distilled water. For seawater, the evaporation efficiency of 69 % is achieved under natural sunlight. Present approach can be applied to any size and shape of the mesh and has great industrial applications.