Fe-C microelectrolysis and magnetic field aided interfacial solar driven water evaporation for efficient volatile pollutants removal from water

Water pollution poses a considerable threat to human life security. In this paper, through the facile spray-coating approach to prepare Fe-C filler/carbon dots/polydopamine composite (Fe-C/CDs/PDA), the magnetic field and microelectrolysis assisted interfacial solar-driven water evaporation (ISDWE) strategy, which is capable of efficiently removing volatile organic chemicals (VOCs) from water, was initially disclosed. Compared with bare Fe-C filler, the water evaporation rate and phenol removal ratio increased to 1.19 kg•m⁻²•h⁻¹ and 75.40 % under 1.0 kW•m⁻² solar irradiation for Fe-C/CDs/PDA. The enhanced solar absorptivity, reduced water evaporation enthalpy, and high wettability achieved by the CDs/PDA coating contributed to the accelerated water evaporation, and the photo-Fenton process induced by the photocatalysis of the CDs/PDA coating played a significant role in improving the phenol removal ratio. Furthermore, the application of a magnetic field led to enhanced water purification performance as accelerated Fe corrosion generated more Fe²⁺, facilitating water evaporation and promoting microelectrolysis reactions. Finally, Fe-C/CDs/PDA also exhibited high purification performance for other volatile chemicals. A relatively high phenol removal efficiency was likewise achieved by regenerating the Fe-C/CDs/PDA composite. It is expected that our magnetic field-microelectrolysis assisted ISDWE approach will lay the foundation for the design of advanced solar water purification systems in future research undertakings.