Nanomaterials and Superhydrophobic Surfaces: An Overview

Nanoscience is the field dedicated to the study and application of tiny-sized particles, typically on the scale of nanometers. Materials with structures at the nanoscale often have unique mechanical, electrical, thermal, and optical properties, which are considered Nanomaterials. The special qualities of nanomaterials lead to their use in a wide range of device applications. Numerous nanodevices have been designed for applications in various industries, including biosensing, electronics, chemical sensing, and health care, etc. In the future, nanomaterials will be beneficial for the food, biotechnology, and medical fields. Lotus leaf-inspired superhydrophobic coating has been used in various industrial applications. Among them, the use of superhydrophobic materials for potential application prospects such as oil-water separation has gained growing interest. Oil and organic pollutants in water pose a severe problem for aquatic life and human beings. The oceanic oil spill accidents and the discharge of immense oil levels in the surroundings of most industries worldwide have been serious environmental problems. The separation of the oil-water mixture is one of the most important applications of superhydrophobic coating. There is a need to develop technology for oil-water separation because the spilled oil affects the ecological and environmental system. However, a simple and low-cost strategy for the fabrication of durable superhydrophobic materials remains a major challenge. Recently, superhydrophobic/superoleophilic sponges, metal meshes, membranes, and porous materials have played crucial roles in separating oil from oil-water mixtures. The micro and nanopores of the substrate facilitate to entry of liquid into it, and superhydrophobic/superoleophilic properties of the substrate surface resist water and allow oil to enter the porous substrate. The coated surfaces exhibit superhydrophobicity with a water contact angle of > 1500 and a sliding angle of nearly 00. The thermal stability, pH tolerance, compression tolerance, chemical durability, reusability, emulsion oil-water separation, and muddy water-oil separation was tested by using these superhydrophobic surfaces. The superhydrophobic surfaces have a sustainable, anti-wetting property under cross-sectional cutting, pressing, paper peel test, abrasion resistance test, and different pH environments. The superhydrophobic surface is suitable for practical application on a large scale.