Xiaopan Qiu,Haoran Kong,Yuting Li,Qinhuan Wang,Yu Wang
Solar-driven interfacial evaporation provides a feasible and sustainable way to solve the fresh water shortage using abundant solar energy and has recently attracted considerable attention. However, it has been limited by the evaporation rate and solar-heat conversion efficiency of the current materials. Herein, a novel Ti4O7 membrane with synergetic photothermal and electrothermal effects was developed using a straightforward in situ approach. Based on interface engineering, the interface between the surface of the membrane and water was hydrophobically modified, and a thermal insulation layer was added to the bottom of the membrane. The optimized self-floating membrane with excellent sunlight absorbability and conductivity achieved a remarkably high evaporation rate of 7.51 kg m–2 h–1 with a voltage of 3 V as compensation under one-sun irradiation (1 kW m–2). Moreover, the bilayered membrane displayed efficient salt ion rejection, and the collected water can meet the World Health Organization (WHO) standard required for potable water.
Preventing ice formation and ice swift removal from the solid surface are essential in numerous application fields. Superhydrophobic coating is an effective way to delay the icing phenomenon. However, the superhydrophobic coating was wetted easily after icing–deicing cycles that led to the failure of anti-icing. In this study, a robust, amphiphobic coating consisted of fluorinated multiwalled carbon nanotubes (FMWCNTs) and commercial polyurethane was constructed by a simply spray process. Because of the addition of FMWCNTs, the coating demonstrated a good amphiphobic feature and highly efficient photothermal conversion, which endowed the coating surface with excellent deicing and defrosting characteristics under sunlight irradiation. In addition, self-cleaning and self-healing properties of the coating under sunlight ensured its efficient photothermal conversion and long service life. To further improve the photothermal deicing effect, a coating system containing a photothermal layer (P), thermal-conductive layer (C), and thermal-protective layer (P) was constructed. The heat generating from the photothermal layer can transfer the whole coating surface by the conductive layer, but with limited transmission to substrate materials by a thermal-protective layer. The coating system can still deice and defrost rapidly on the whole surface and only a small portion of photothermal coating was irradiated under extremely low temperature. The outdoor experiment has confirmed that the coating melted and removed snow rapidly in a winter environment. The multifunctional photothermal deicing coating may have a wide application in outdoor surrounding.