Nanoparticle-filled oriented nanofiber membrane for effective emulsion separation via spin coating

Patterned membranes, particularly those modified with nanoparticles, are commonly used in the effective filtration separation of emulsions. However, the conventional fabrication methods are based on wet spinning that require large quantities of organic solvents, necessitating treatment and recycling. This increases the economic and environmental cost, damages the environment, and lowers the production efficiency. In this study, we develop a novel spin-coating method to directly fabricate oriented and patterned nanofiber membranes from powders without harsh solution treatment. The patterned nanofiber membrane exhibits a higher flux than a traditional porous membrane with disordered nanofibers and the same retention rate. The use of oriented nanofiber membranes filled with multi-walled carbon nanotubes and graphene enhances the emulsion-breaking effect during emulsion separation. The effect of the type and diameter of the nanofibers on the orientation degradation of the oriented nanofiber membrane is analyzed. The combination of nanofiber membranes with nanoparticles enables the design and synthesis of composite nanofiber membranes with precisely tailored pore structures for various applications.