A smart “on-off” 3D multifunctional material with adjustable wettability for wastewater treatment

In this work a smart “on-off” 3D multi-functional pore material was prepared through simple, economic and environmental protection methods, realizing the purpose of efficient oil–water separation and controllable recovery, organic pollutant catalysis and antibacterial treatment. Specifically, the smart 3D porous material can be controlled by different pH values to achieve repeated switching between hydrophilicity and hydrophobicity, thus completing the separation and recovery of oil. In addition, it exhibits rapid adsorption/resolution behavior, good separation efficiency, high adsorption capacity (up to 44–83 times its own dry weight or above 65 %-101 % of its own volume for various oils/organic solvents), stable hydrophobicity and reusability. Notably, the adsorption capacity of 81 % is still maintained after 100 cyclic adsorption extrusion experiments. More importantly, the target material can realize the separation of a variety of oils, especially its excellent antibacterial performance and catalytic dyestuff performance, which is more suitable for the complex water environment in practical applications. Even more exciting that the target material is finished by dipping, the preparation process is simple and the cost is low. These advantages are targeted to solve the problems concerned in industrial production and practical applications.