Durable self-cleaning PVDF coating with photocatalysis and superhydrophobic property based on hierarchical coral-like 2D g-C3N4/1D TiO2 hybrid

The low-availability of visible light and poor durability of photocatalytic superhydrophobic coatings are two major challenges for practical applications. In this paper, a heterojunction structure was formed by using the force assembly between two-dimensional graphitic carbon nitride (2D g-C3N4） and one-dimensional titanium dioxide nanorods (1D TNr）, and then the surface was modified by 1 H, 1 H, 2 H, 2 H-perfluorodecyltriethoxysilane (PFDTS). MGT (Modified g-C3N4/TNr Heterojunction Composite) heterojunction was uniformly dispersed in the PVDF/PTFE mixture to form a coating that can be easily applied for spraying. MGT has superior charge carrier separation and high visible light absorption, which endows the MGT/PVDF/PTFE coating with exceptional performance in visible photocatalytic degradation of pollutants. The micro-nano 3D structure with low surface energy constructed by MGT and PVDF/PTFE contributes to the superhydrophobicity of the coating. The outstanding visible light photocatalytic and superhydrophobicity provide the coating with highly efficient self-cleaning performance. Impressively, the coating presents remarkable abrasion resistance and resistance to harsh environments such as acids, alkalis, salts, and UV irradiation thanks to the firm adhesion of MGT, the excellent solvent, and oxidation resistance of PVDF/PTFE. Therefore, this durable and highly efficient photocatalytic superhydrophobic coating is expected to be produced industrially and applied on a large scale.