Enhanced interfacial evaporation and desalination by solar heat localisation using nitrogenated graphitic carbon and Co3O4 nanorods

The problem of worldwide scarcity of clean water can be resolved efficiently by utilizing the significant heat localizing capability of the solar-driven interfacial evaporator with a nominal impact on the environment. A novel flexible, recyclable, hydrophilic photothermal composite membrane containing a blend of mesoporous Co3O4 nanorod and nanoporous nitrogen-doped graphitic carbon hollow spheres has been proposed. The composite membrane exhibits an enhanced broadband optical absorption which leads to a high interfacial evaporation rate (2.28 kg m2 h-1) and a notable solar-to-steam generation efficiency (93%) under sunlight (900 W/ m2) at 3.5 wt% NaCl salinity. The lower salt accumulation on the evaporation surface and the remarkable recyclability of the photothermal membrane under sunlight prove its practical usability in the desalination of seawater, water purification, salt production, and solar energy harvesting.

Automated summary

The worldwide scarcity of clean water can be efficiently resolved by the solar-driven interfacial evaporator, which has a significant heat localizing capability and minimal impact on the environment. A novel flexible and recyclable hydrophilic photothermal composite membrane, containing a blend of mesoporous Co3O4 nanorod and nanoporous nitrogen-doped graphitic carbon hollow spheres, exhibits enhanced broadband optical absorption, resulting in a high interfacial evaporation rate (2.28 kg m2 h-1) and remarkable solar-to-steam generation efficiency (93%) under sunlight (900 W/ m2) at 3.5 wt% NaCl salinity. The lower salt accumulation on the evaporation surface and the remarkable recyclability of the photothermal membrane under sunlight demonstrate its practical usability in seawater desalination, water purification, salt production, and solar energy harvesting.