Superwetting interfaces for oil/water separation

Superhydrophobic coatings have been applied in various fields. The materials used in the preparation of superhydrophobic coatings have attracted the attention of scholars. Due to the harm of fluorine-containing substances with low surface energy to the environment, fluorine-free superhydrophobic coatings have become a hotspot in the research field. Herein, a fluorine-free superhydrophobic coating with oil/water separation was made by a solution immersion way. The fluorine-free copolymer and polydimethylsiloxane (PDMS)/SiO2 nanoparticles (NPs) were mixed to prepare a composite solution, and the superhydrophobic surface was obtained on the paper by a dipping method. The scanning electron microscope, x-ray photoelectron spectrometer, 1H nuclear magnetic resonance, and Fourier transform infrared were used to study the surface characteristics and structural composition of the superhydrophobic material. The research proved that the copolymer and PDMS/SiO2 NPs were successfully coated on the paper surface, and the rough structure of the superhydrophobic surface was also attributed to the introduction of the copolymer and PDMS/SiO2 NPs. The evaluation of the coating has proved its excellent hydrophobicity, oil/water separation performance, and self-cleaning performance. The coating is a sustainable and environmentally friendly superhydrophobic material that can be used in packaging, construction, petrochemical, and other industries.