Preparation of Superhydrophobic P-TiO2-SiO2/HDTMS Self-Cleaning Coatings with UV-Aging Resistance by Acid Precipitation Method
The superhydrophobic coatings for outdoor use need to be exposed to sunlight for a long time; therefore, their UV-aging resistances are crucial in practical applications. In this study, the primary product of titanium dioxide (P-TiO<sub>2</sub>) was used as the raw material. Nano-silica (SiO<sub>2</sub>) was coated onto the surface of P-TiO<sub>2</sub> by the acid precipitation method to prepare P-TiO<sub>2</sub>-SiO<sub>2</sub> composite particles. Then, they were modified and sprayed simply to obtain a superhydrophobic P-TiO<sub>2</sub>-SiO<sub>2</sub>/HDTMS coating. The results indicated that amorphous nano-SiO<sub>2</sub> was coated on the P-TiO<sub>2</sub> surface, forming a micro-nano binary structure, which was the essential structure to form superhydrophobic coatings. Additionally, the UV-aging property of P-TiO<sub>2</sub> was significantly enhanced after being coated with SiO<sub>2</sub>. After continuous UV irradiation for 30 days, the color difference (ΔE*) and yellowing index (Δb*) values of the coating prepared with P-TiO<sub>2</sub>-SiO<sub>2</sub> increased from 0 to 0.75 and 0.23, respectively. In contrast, the ΔE* and Δb* of the coating prepared with P-TiO<sub>2</sub> increased from 0 to 1.68 and 0.74, respectively. It was clear that the yellowing degree of the P-TiO<sub>2</sub>-SiO<sub>2</sub> coating was lower than that of P-TiO<sub>2</sub>, and its UV-aging resistance was significantly improved. After modification with HDTMS, the P-TiO<sub>2</sub>-SiO<sub>2</sub> coating formed a superhydrophobic P-TiO<sub>2</sub>-SiO<sub>2</sub>/HDTMS coating. The water contact angle (WCA) and water slide angle (WSA) on the surface of the coating were 154.9° and 1.3°, respectively. Furthermore, the coating demonstrated excellent UV-aging resistance. After continuous UV irradiation for 45 days, the WCA on the coating surface remained above 150°. Under the same conditions, the WCAs of the P-TiO<sub>2</sub>/HDTMS coating decreased from more than 150° to 15.3°. This indicated that the retention of surface hydrophobicity of the P-TiO<sub>2</sub>-SiO<sub>2</sub>/HDTMS coating was longer than that of P-TiO<sub>2</sub>/HDTMS, and the P-TiO<sub>2</sub>-SiO<sub>2</sub>/HDTMS coating's UV-aging resistance was greater. The superhydrophobic P-TiO<sub>2</sub>-SiO<sub>2</sub>/HDTMS self-cleaning coating reported in this study exhibited outstanding UV-aging resistance, and it had the potential for long-term outdoor use.
Authors
- Daimei Chen (ORCID: https://orcid.org/0000-0002-2327-902X)
- Hao Ding (ORCID: https://orcid.org/0000-0002-5925-190X)
- Xuefeng Bai (ORCID: https://orcid.org/0000-0002-8757-7034)
- Xuan Wang (ORCID: https://orcid.org/0000-0003-4820-2368)
- Le Zhang (ORCID: https://orcid.org/0000-0003-4932-8499)
- Ying Liu (ORCID: https://orcid.org/0000-0002-7292-3221)
- Yihe Zhang (ORCID: https://orcid.org/0000-0002-1407-4129)
Institutions
- University of Nottingham (GB)
- China University of Geosciences (Beijing) (CN)
Publication Details
- Journal
- Nanomaterials
- Published
- 2025-07-20
- DOI
- https://doi.org/10.3390/nano15141127
- Primary Topic
- Silicone and Siloxane Chemistry
- Type
- article
- Field-Weighted Citation Impact
- 0.00