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. The 1D Fe/C constructed Janus photothermal conversion membrane combining metal plasmon resonance and the molecular thermal vibrations of carbon nanomaterials has high photothermal conversion efficiency and interfacial water evaporation rate. The membrane also exhibits outstanding salt resistance and excellent ion-removal ability, demonstrating a promising sustainable energy-saving technology for practical seawater desalination and wastewater purification.