Photothermal-driven thermal Marangoni effect-enhanced membranes for high-efficiency emulsion separation

To address the challenges of low flux and fouling susceptibility in conventional membrane technologies for emulsified liquid separation, this study proposes a novel emulsion separation strategy based on the photothermal effect-induced thermal Marangoni phenomenon. By integrating photothermal nanomaterials (Molybdenum disulfide) on the surface of coal-based fiber membrane (CFM), thermal Marangoni convection was triggered by localized temperature gradients generated via photothermal conversion, which significantly enhanced the migration and coalescence of droplets consequently. Under xenon lamp irradiation, the photothermal-assisted membrane achieved a separation flux of 1503.9 L m−2 h−1, representing a 3.5-fold enhancement compared to unirradiated conditions. Mechanistic analysis reveals that the synergy between photothermal and Marangoni effects effectively mitigates concentration polarization and suppresses membrane fouling. This work provides a new pathway for developing energy-efficient, high-flux smart separation membranes, with promising applications in oily wastewater treatment and industrial chemical separation.