Self-cleaning SiO₂-TiO₂ ceramic membrane for enhanced oil-water separation

An efficient and practical method is proposed for the separation of oil-water mixtures and emulsions in sustainable water ecosystems, facilitating energy recovery. The construction of flexible ceramic fiber membranes with high throughput and self-cleaning capabilities has proven effective but challenging. This study reports a novel approach combining the sol-gel and electrospinning techniques to synthesize flexible silicon dioxide (SiO2)-titanium dioxide (TiO2) nanofiber membranes (STNFMs). These membranes possess nanoscale rough structures, granting them superhydrophilicity and underwater superoleophobicity (155 degrees). Exploiting the photocatalytic properties of titanium dioxide, STNFMs-4 not only demonstrates excellent separation performance but also exhibits remarkable self-cleaning abilities. After 2 h of ultraviolet light irradiation, the membrane flux returns to its original level. STNFMs provide a promising solution for highly efficient separation of oil-water mixtures and emulsions, with the potential to play a significant role in water treatment and resource recovery.