Papers by Keyword: Mesoporous Titania

Abstract: Titania (TiO₂) is one of the most unique catalysts, crucially important in photo-green chemistry. The mesoporous TiO₂ has large surface area, uniform pore size and open frameworks for the transfer of mass and charges. TiO₂ has photocatalytic activity which can degrade both organic and inorganic compounds. The band gap energy of TiO₂ can be modified by doping various metal oxides to make it tunable for application in solar cells. Various catalytic metals such as Au, Pt and Pd can be synthesized on TiO₂ surface to enlarge its application in various catalytic molecular transformations. Thus TiO₂ has promising application in the production of the renewable energy, degradation of environmentally hazardous components, generation of solar cells and sensors. A large number of efforts have been made to synthesize mesoporous TiO₂ materials with high surface area and uniform pore size. However, they were not cost effective for applications in environment and green energy generation. The photocatalytic actions of TiO₂ can further kill or transform harmful microorganisms into harmless or less harmful ones. This paper reviewed synthesis methodology of silica supported mesoporous TiO₂ and their applications in environmental photocatalysis and solar cells.

Abstract: 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.

Abstract: In order to avoid the damage on mesostructure by the high temperature treatment, inorganic titanium species were used as the precursors for the preparation of mesoporous TiO2 of crystalline framework at mild conditions. The influences of the precursor, additive, reaction pH and temperature on phase and textural structures of the products were investigated. The samples were characterized by XRD, N2 adsorption/desorption, FT-IR and SEM. The results show that anatase mesoporous TiO2 with large surface area could be obtained without calcination with Ti(SO4)2 as precursor or TiCl4 when SO42- was added. And the template could be completely removed by Soxhlet extraction.

Abstract: A heterojunction structure between a cubic structured mesoporous titania thin film and polythiocyanogen inside the pores was prepared by electrodeposition technique. UV-Vis absorption and FT-IR spectra show that the electrodeposited material is polythiocyanogen and the SEM images show that polythiocyanogen is infiltrated into the pores of the mesoporous titania film. In addition, this heterojunction structure was fabricated into a photovoltaic cell and the cell performance was tested. The cell showed an overall efficiency of 0.03%.