Fabrication of sericite-TiO2/HDTMS superhydrophobic self-cleaning coatings by hydrothermal method

The superhydrophobic surface like lotus leaf had important application prospects in the field of self-cleaning of building exterior walls. However, its single function and poor UV-aging resistance severely limited its practical application. In this study, sericite, an inorganic UV-shielding material with UV absorption properties, was selected as carrier to prepared sericite-TiO 2 composite particles by hydrothermal method. Then, it was modified with hexadecyltrimethoxysilane (HDTMS) and sprayed onto the substrate’s surfaces, forming a superhydrophobic coating with photocatalytic performance and UV-aging resistance. The results showed that the prepared nano-TiO 2 was rutile and uniformly loaded on the sericite surface. The sericite-TiO 2 /HDTMS coating exhibited lotus-like superhydrophobic property with water contact angle (WCA) and water slide angle (WSA) of 154.7° and 2.1°, respectively. The coating also showed photocatalytic performance, and 35.8% of 10 ppm methyl orange solution can be degraded under UV light in 50   min. Due to the fact that sericite was an inorganic UV-shielding agent, the as-prepared coating showed UV-aging property. After UV irradiation for 40   h, WCA of the surface still approach 150°. The sericite-TiO 2 /HDTMS coating not only had self-cleaning performance and UV-aging property, but also the potential for practical applications.