UV-Resistant and Thermally Stable Superhydrophobic CeO₂ Nanotubes with High Water Adhesion

A novel type of sticky superhydrophobic cerium dioxide (CeO₂ ) nanotube material is prepared by hydrothermal treatment without any chemical modification. A water droplet on the material surface shows a static water contact angle of about 157° but the water droplet is pinned on the material surface even when the material surface is turned upside down. Interestingly, the as-prepared CeO₂ nanotube material displays durable superhydrophobicity and enhanced adhesion to water under ultraviolet (UV) light irradiation. Importantly, this change in water adhesion can be reversed by heat treatment to restore the original adhesive value of 20 µL. Further, the maximum volume of the water droplet adhered on the material surface of CeO₂ nanotubes can be regulated without loss of superhydrophobicity during the heating treatment/UV-irradiation cycling. Meanwhile, the superhydrophobic CeO₂ nanotube material shows remarkable thermal stability even at temperatures as high as 450 °C, long-term durability in chemical environment, and air-storage and good resistance to oily contaminant. Finally, the potential application in no-loss water transportation of this sticky superhydrophobic CeO₂ material is demonstrated.