TDI/TiO₂ Hybrid Networks for Superhydrophobic Coatings with Superior UV Durability and Cation Adsorption Functionality

Abstract

Durability under UV illumination remains a big challenge of TiO 2 -based superhydrophobic coatings, with the photocatalytic effect causing degradation of low-surface-energy material over time, resulting in the surfaces losing their hydrophobicity. We report surfaces made from tolylene-2,4diisocyanate (TDI)/TiO 2 hybrid networks that demonstrate superhydrophobicity and superior UV durability. Structural and morphological studies reveal that the TDI/TiO 2 hybrid networks are composed of TiO 2 nanoparticles interconnected with TDI bridges and then encapsulated by a TDI layer. Through controlling the fraction of TDI in the synthesis process, the thickness of the TDI encapsulation layer around the TDI/TiO 2 hybrid networks can be varied. When the weight ratio of TDI/TiO 2 is 5:1, the superhydrophobicity of the hybrid network surface remains almost unchanged after a month of continuous UV illumination. This hybrid network surface can also clean methylene blue solution through the synergistic effects of cation adsorption and photocatalysis, holding promising potential for applications toward reducing cation pollutions in both liquid and air environments.

Hierarchical Flower-Like Hollow SiO2@TiO2 Spheres with Enhanced Thermal Insulation and Ultraviolet Resistance Performances for Building Coating

“…(II) Physical structure. A large number of interfacial pores in the PA/FHSTs composite film, the heterostructural shell, and hollow core of the FHSTs were all conductive to the multilevel reflection and scattering of ultraviolet light …”

Superhydrophobic Hierarchical Structures from Self-Assembly of Cellulose-Based Nanoparticles

“…Various agents, such as polydopamine, epoxy resin, poly­(dimethylsiloxane), and polyurethane, have been widely used as adhesive agents to enhance the mechanical stability of superhydrophobic surfaces. ,− Here, a fully esterified UCE with a DS of 3 (UCE 3 ) was used as an adhesive agent to improve the mechanical stability of SH-UCE 1.9 . A similar synthesis procedure obtained UCE 3 with UCE 1.9 .…”

Photocatalytic Superamphiphobic Coatings and the Effect of Surface Microstructures on Superamphiphobicity

“…Among them, FTS-0 coating can still maintain excellent superamphiphobicity after 14 days of UV aging, and the ACA of the four liquids is still greater than 150°. While the oleophobicity of FTS-100 decreased greatly after 3 d of UV irradiation, the water ACA of FTS-100 decreased to near 150°after 7 d. This is mainly due to the strong oxidation groups produced by TNs under UV irradiation, which breaks the C-F bond on the surface of the FTS coating, 34,37 increasing the surface energy and decreasing the superamphiphobicity.…”

“…Wettability and durability play a decisive role in the application effect of coatings. 33,34 The water ACA of all the FTS coatings with different TNs contents is more than 150°, and the HA is less than 10°, which shows superhydrophobic properties (see Figure 5). However, for organic matter (ethylene glycol and glycerol) and oil (olive oil), the ACA decreases and the HA increases slightly, especially for FTS-100 with a high TNs content.…”