Substrate-independent multifunctional nanostructured coating for diverse wastewater treatment

Development of multifunctional superwettable materials that can efficiently separate both insoluble and soluble organic pollutants from wastewater are imperative, but remain challenging. Herein, a substrate-independent coating strategy is proposed for developing multifunctional superwettable materials, using a simple and cost-effective method. A three-dimensional (3D) porous honeycomb Ni–Co layered double hydroxide (LDH) nanostructured coating can impart positive charges and robust superhydrophilicity to various substrates, including metal meshes and inorganic and organic materials. This approach provides multifunctional materials for diverse wastewater treatments, such as immiscible oil/water mixtures, oil/water emulsions, and organic dyes. The as-prepared superhydrophilic materials exhibit remarkable underwater superoleophobicity and oil repellency. Thus, the materials exhibit high-performance separation capabilities for immiscible oil/water mixtures and oil/water emulsions. Additionally, the as-resulted materials achieve good adsorption properties for water-soluble anionic dyes. Moreover, the versatile multifunctional nanostructure-coated materials, which possess exceptional environmental durability and thermal stability, exhibit potential application prospects in real-world wastewater treatment.