Based on (3-methacryloxypropyl)-Polyhedral oligomeric silsesquioxane (MP-POSS) (MP), vinyl-POSS (VP), (3-glycidoxypropyl)-POSS (GP) and modified with 5, 10, 15, 20 and 25 wt-% titanium tetrabutoxide (TTB), three hybrid nanofilms (f-MPT, f-VPT and f-GPT) were prepared using hydrolytic condensation and crosslinking. The transparency of the films was measured at the ranges of ultraviolet A (UV-A) (320-400 nm) spectrum which can cause a much greater risk of skin changes. The average transparency (AT) values of three films were about 65-78% (320-350 nm) and 85-89% (350-400 nm), which implies that these films indeed can provide a physical barrier for blocking the UV-A absorbed into the skin, indicating functionality of the POSS/TiO2 materials as the sun protection factor (SPF) ingredients in a sunscreen. The AT values of three films were in the order of f-MPT>f-GPT>f-VPT due to complete-cage structures of building blocks (POSS) and the size of organic branches covalently bonded to the silica network in the molecular structures. This indicates that VPT powder might be significantly better to selected for the SPF. The TTB addition results in the hybrid structure containing TiO2 which causes a decrease in the AA radiation from sunlight. Lower transparency of the films containing 25 wt-% TTB fractions is ascribed to more amounts of TTB in the modified films.

Nb-doped TiO2 powders with different concentrations of Nb have been synthesized by a sol-gel method and characterized by a series of technologies including X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV-vis spectroscopy. The photocatalytic activity of Nb-doped TiO2 is evaluated by degradation efficiency of methyl orange in aqueous solution. The results indicate that the photocatalytic activity of Nb-doped TiO2 synthesized with a Nb/Ti molar ratio of 5% is higher than that of TiO2 under the visible light.

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Highly ordered mesoporous TiO2 was synthesized by a hydrolysis condensation process using block copolymer P123 as the template and tetrabutyl orthotitanate (TBOT) as titanium precursor.The influences of the synthesis parameters including the volume of solvent, the ratio of the template to TBOT and reaction pH on the structure were investigated. The structure properties of the products were characterized with low-angle XRD, FT-IR, N2 adsorption-desorption analysis. The results showed that the amount of solvent played a decisive role for the formation of ordered pore structure. The proper hydrolysis pH is in neutral and acidic range. The template can be removed totally by Soxhlet extraction with ethanol and the mesoporous structure can be retained perfectly by this template removal method. The product has the BET surface area of 266.5m2/g and a narrow pore distribution with a peak at 4.34 nm.