One-dimensional Fe/C constructed Janus membrane enables highly-efficient and stable solar-driven interfacial evaporation

The practical use of solar-driven interfacial evaporation is hampered by high cost, low photothermal conversion efficiency, and poor stability. Herein, a one-dimensional Fe/C constructed photothermal membrane is rationally developed to replace precious metals via the combination of Fe plasmon resonance with carbon molecular thermal vibration. The membrane exhibits excellent light absorbance (95.72 ​%) and water evaporation rate (2.60 ​kg ​m⁻² ​h⁻¹) leading to photothermal conversion efficiency up to 95.65 ​% under 1 sun illumination. Janus Fe/C membrane with superhydrophobic and hydrophilic structure is further prepared by polydimethylsiloxane (PDMS) coating to improve long-term stability. The evaporation rate can be maintained at over 90 ​% after 80 ​h illumination for real seawater treatment with metal ion removal efficiency >99 ​%. It also shows high evaporation performance and stability for organic solvents such as IPA, and NMP. Thus, the 1D Fe/C constructed Janus membrane is a promising candidate for energy-saving solar-driven interfacial solvent evaporation including seawater desalination, wastewater treatment, and organic solvent purification.