Flexible and highly efficient bilayer photothermal paper for water desalination and purification: self-floating, rapid water transport, and localized heat

ABATRACT: In view of the sustainable and environmentally friendly characteristics of solar energy, solar water evaporation has been identified as a promising approach to mitigate the global water crises. However, it is still a great challenge to develop a portable, flexible, scalable, and high performance solar water evaporation material. Herein, a bilayer structured solar water evaporation material, consisting of a top multi-walled carbon nanotubes (MWCNTs) layer and a bottom polyphenylene sulfide/ fibrillated cellulose (PPS/FC) paper, was fabricated via a simple vacuum filtration technology for efficient solar water evaporation. The MWCNTs layer performs as a light absorber with a high solar absorptance (about 93%) in the wavelength range from 400 to 1200 nm and good light-to-heat conversion capability, while the bottom layer (porous network structured PPS/FC paper) exhibits excellent water transporting ability, high temperature stability, and good thermal insulating capability (0.0467 W m-1 K-1). Benef...