Facile approach to fabricate a high-performance superhydrophobic PS/OTS modified SS mesh for oil-water separation

Special wetting materials have been used for the oil and water separation due to their different interfacial attraction of oil and water. Herein, we successfully fabricated superhydrophobic coatings on stainless steel (SS) mesh by depositing successive layers of polystyrene (PS) and octadecyltrichlorosilane (OTS) through the dip-coating method. The as-prepared coating showed a water contact angle (WCA) of 157.5 ± 2°, a rolling angle of 6 ± 2° and an oil contact angle (OCA) of around 0°. The surface microstructure analysis of the coating revealed a regular pattern of microscale bumps with nanoscale folds on it, both of which improve the overall superhydrophobicity of the surface. The capacity of coatings to separate oil and water was examined by employing a variety of mixtures of oil and water, including petrol, diesel, kerosene, vegetable oil, and coconut oil. In case of low viscosity oil, the coated mesh demonstrated separation effectiveness of more than 97% and on the other hand, high viscosity oil demonstrated just 89% efficiency. Low viscosity oils showed a greater permeation flux through the mesh than extremely viscous oil. The mechanical strength of the coating was examined using bending, twisting, adhesive tape testing, sandpaper abrasion tests, and the findings indicated that coated mesh had exceptional mechanical resilience. In addition, the developed superhydrophobic mesh demonstrated excellent thermal stability and self-cleaning properties. Therefore, this superhydrophobic/superoleophilic mesh has a significant deal of application potential in practical.