Facile preparation of self-floating photothermal membranes with simultaneous mechanical stability and antibacterial activity for solar-driven interfacial water evaporation is regarded as a practical approach for clean water production. Herein, a robust porous bi-layered photothermal membrane (carbon nanotube@polyethylene imine/mixed cellulose esters, CNT@PEI/MCE), where the top solar conversion layer of pristine CNTs is seamlessly connected to the bottom heat transfer barrier layer of hydrophilic MCE, is facilely prepared via a simple vacuum filtration. With the synergistic integration of MCE-mediated heating localization, CNT-mediated solar-heating, PEI-mediated hygroscopicity and noncovalent interactions, the CNT@PEI/MCE membrane can stay at the water–air interface with Wenzel's wetting behavior and can thus achieve a high interfacial water evaporation efficiency (72%) and a rapid evaporation rate (4.23 times higher than that of pure water) under simulated solar irradiation. Meanwhile, the CNT@PEI/MCE membrane exhibits good mechanical stability, strong operability, distinct antibacterial activity and high durability. This advanced membrane, together with its cost-effectiveness, provides a practical sustainable energy technique for clean water production.

Porous MoS₂ nanoflower-containing hydrogels are proposed as enhanced light trapping and antibacterial photothermal hotspots and are facilely deposited on a hydrophilic MCE substrate for highly efficient solar-driven interfacial water evaporation.

The complex aerogel generated from nano-polysaccharides, chitin nanocrystals (ChiNC) and TEMPO-oxidized cellulose nanofibers (TCNF), and its derivative cationic guar gum (CGG) is successfully prepared via a facile freeze-drying method with glutaraldehyde (GA) as cross-linkers. The complexation of ChiNC, TCNF, and CGG is shown to be helpful in creating a porous structure in the three-dimensional aerogel, which creates within the aerogel with large pore volume and excellent compressive properties. The ChiNC/TCNF/CGG aerogel is then modified with methyltrichlorosilane (MTCS) to obtain superhydrophobicity/superoleophilicity and used for oil–water separation. The successful modification is demonstrated through FTIR, XPS, and surface wettability studies. A water contact angle of 155° on the aerogel surface and 150° on the surface of the inside part of aerogel are obtained for the MTCS-modified ChiNC/TCNF/CGG aerogel, resulting in its effective absorption of corn oil and organic solvents (toluene, n-hexane, and trichloromethane) from both beneath and at the surface of water with excellent absorption capacity (i.e., 21.9 g/g for trichloromethane). More importantly, the modified aerogel can be used to continuously separate oil from water with the assistance of a vacuum setup and maintains a high absorption capacity after being used for 10 cycles. The as-prepared superhydrophobic/superoleophilic ChiNC/TCNF/CGG aerogel can be used as a promising absorbent material for the removal of oil from aqueous media.