Robustly Adherable Hierarchical Nanostructures via Self-Bonding and Self-Texturing of Aluminum Nitride for Applications in Highly Efficient Oil/Water Separation.

The release of wastewater containing oily contaminants into water bodies and soils severely threatens the environment and human health. Although several conventional techniques are used in treating oil/water mixtures and emulsions, these methods are often expensive, time-consuming, and inefficient. Porous membranes or sponges are widely used in filtration or absorption, but their use is limited by their low separation efficiencies and secondary contamination. Recently, a novel technology that is designed to selectively separate oil from oil/water mixtures or emulsions by using materials with special wetting surfaces was developed. Superwetting surfaces may be used to selectively separate oils from emulsions. This approach enables the use of materials with relatively large pores, resulting in high throughput properties and efficiencies. In this study, a facile method is proposed for use in preparing a superhydrophobic-superoleophilic felt fabric for utilization in separating oil/water mixtures and emulsions. By hydrolyzing aluminum nitride nanopowders, the desired micro-/nanostructures may be successfully fabricated and firmly attached to a fabric surface without using a binder resin. This results in various materials with special wetting properties, regardless of their sizes and shapes and the successful separation of oil and water from oil/water mixtures and emulsions in harsh environments. This approach exhibits promise as a low-cost, scalable, and efficient method of separating oily wastewater, with the potential for use in wider industrial applications.