Preparation of Nano-TiO(2)-Coated SiO(2) Microsphere Composite Material and Evaluation of Its Self-Cleaning Property

In order to improve the dispersion of nano-TiO(2) particles and enhance its self-cleaning properties, including photocatalytic degradation of pollutants and surface hydrophilicity, we prepared nano-TiO(2)-coated SiO(2) microsphere composite self-cleaning materials (SiO(2)–TiO(2)) by co-grinding SiO(2) microspheres and TiO(2) soliquid and calcining the ground product. The structure, morphology, and self-cleaning properties of the SiO(2)–TiO(2) were characterized. The characterization results showed that the degradation efficiency of methyl orange by SiO(2)–TiO(2) was 97%, which was significantly higher than that obtained by pure nano-TiO(2). The minimum water contact angle of SiO(2)–TiO(2) was 8°, indicating strong hydrophilicity and the good self-cleaning effect. The as-prepared SiO(2)–TiO(2) was characterized by the nano-TiO(2) particles uniformly coated on the SiO(2) microspheres and distributed in the gap among the microspheres. The nano-TiO(2) particles were in an anatase phase with the particle size of 15–20 nm. The nano-TiO(2) particles were combined with SiO(2) microspheres via the dehydroxylation of hydroxyl groups on their surfaces.