Fabrication of cement-based superhydrophobic coatings with enhanced self-cleaning property, chemical stability, and UV-radiation resistance

Abstract

Superhydrophobic coatings (SCs) can potentially reduce dust accumulation on the structure surfaces and mitigate environmental corrosion.In this study, a superhydrophobic coating composed of nano-SiO2, N-octyltriethoxysilane, and silane coupling agent was prepared for cement-based structures by green sol–gel method. By means of SEM, FTIR, XRD, EDS, and XPS, it was proved that cement-based superhydrophobic coatings were successfully formed on the surface of cement-based substrate. Two different techniques (brushing and replication) were used for fabricating cement-based superhydrophobic coatings (CBSCs), and their optimum preparation conditions were determined via orthogonal experiments. The obtained results revealed that the contact angle (CA) and sliding angle (SA) of the fabricated SCs reached 153° and 4°, respectively. Furthermore, the CBSCs exhibited outstanding self-cleaning properties and mechanical stability. Moreover, the chemical stability and UV-radiation resistance of the fabricated CBSCs were significantly improved compared with ordinary concrete.