共沉淀法制备氧化硅改性的纳米二氧化钛及其性质

Preparation and Characterization of Silica-modified Titanium Dioxide Nanoparticles by Co-precipitation Method

采用共沉淀法合成了氧化硅改性的具有高比表面积的纳米二氧化钛.氧化硅的添加提高了二氧化钛纳米颗粒的热稳定性能,有效地抑制了纳米二氧化钛的颗粒增长、团聚和锐钛向金红石的晶型转换.光催化降解亚甲基蓝证明,样品具有较高的光催化活性,而且随着氧化硅添加量的增加,光催化活性提高.

Silica-modified titanium dioxides were prepared by co-precipitation method and then characterized by XRD, FT-IR, XPS, TEM, and UV-Vis absorption spectroscopy. The results showed that there was a strong interaction between SiO2 and TiO2, and Ti-O-Si bonds formed on silica-modified titanium dioxide surfaces. The addition of silica in TiO2 particle could effectively suppress the formation of rutile phase, the decrease of surface area and the growth of titanium dioxide crystals. The band-gap transition increased with the increase of silica content. In comparison with pure TiO2 nanoparticles, the silica-modified TiO2 nanoparticles exhibited better photocatalytic activity, and the activity increased with the silica content.