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Abstract: Bi-doped hollow titania spheres were prepared using carbon spheres as template and Bi-doped titania nanoparticles as building blocks. The Bi-doped titania nanoparticles were synthesized at low temperature. The prepared hollow spheres were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), UV–vis diffuse reflectance spectrum (DRS) and X-ray photoelectron spectroscopy (XPS). The effects of Bi content on the physical structure and photocatalytic activity of doped hollow titania sphere samples were investigated. Results showed that there was an optimal Bi-doped content (4%) for the photocatalytic degradation of methylene blue (MB). [Copyright &y& Elsevier]

Abstract: N-doped titania hollow spheres (NTHS) were prepared by a one-pot hydrothermal method using urea as precursor of nitrogen. The prepared hollow spheres were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), scanning electron microscope (SEM), Brunauer–Emmett–Teller (BET), X-ray photoelectron spectroscopy (XPS) and UV–vis diffuse reflectance spectrum (DRS). The photocatalytic activity of as-prepared titania hollow spheres was determined by degradation of Reactive Brilliant Red dye X-3B (C.I. reactive red 2) under visible light irradiation, and was compared to non-doped titania hollow spheres and commercial P25 titania. Results indicated that the as-prepared NTHS showed highest photocatalytic activity. [Copyright &y& Elsevier]

Abstract: A novel photocatalyst (Ce, C-codoped titania) was synthesized through a modified sol–gel method under mild condition. The as-prepared sample was investigated by XRD, SEM, DRS and XPS. It was found that the as-prepared photocatalyst was composed of spheroidal particles, which were smaller than undoped ones. The absorbance spectrum of Ce, C-codoped TiO2 exhibited significant red-shift to visible region. It can be ascribed to appearance of a new electronic state in the middle of the TiO2 band-gap. Furthermore, cerium doping could slow the radiative recombination process of photogenerated electrons and holes in TiO2. Accordingly, for degradation of dye Reactive Brillint Red X-3B (C.I. reactive red 2) under visible light, the photocatalytic activity of Ce, C-codoped TiO2 improved much compared to other samples (C-doped TiO2, undoped TiO2 and P25). [Copyright &y& Elsevier]

Abstract: Nanocrystalline mesoporous titania was synthesized via a combined sol–gel process with surfactant-assisted templating method using cetyltrimethyl ammonium bromide (CTAB) as the structure-directing agent. The process was catalyzed by different acid (hydrochloric acid, nitric acid, sulfuric acid, or phosphoric acid). The prepared samples were characterized by XRD, TEM, BET and FT-IR. The photocatalytic activity of the samples was determined by degradation of phenol in aqueous solution. Results showed that different acid had different effect on the structure and crystal phase of the samples. The sample adjusted by phosphoric acid showed highest surface area and photocatalytic activity. The formation mechanism of the samples catalyzed by different acid was also discussed. [Copyright &y& Elsevier]

Abstract: Anatase titania-activated carbon composite film was prepared by a simple method at low temperature (75°C at most). The film was characterized by XRD, SEM and BET analysis. Results showed that the composite film was porous because it formed a nano-micro structure. The photocatalytic activity of the composite film was determined by degradation of 4-cholophenol (4-CP) under UV irradiation, and was compared to pure titania film and P25 film. It exhibited that the photocatalytic activity of composite film enhanced a lot. The recycle ability of the composite film was also investigated. The degradation ratio which was still higher than 85% after 5 cycles, decreased only 3% compared to the first cycle. [Copyright &y& Elsevier]

Hierarchical double-shell WO 3 microspheres (HDS-WO 3 ) have been successfully obtained through the thermal decomposition of WO 3 ·H 2 O formed by metal salts as the templates. The products were characterized by X-ray diffraction (XRD), and the morphology was investigated by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). In addition, the HDS-WO 3 microspheres were analyzed by the Thermogravimetric (TG) and Brunauer-Emmett-Teller (BET) analysis. The synthetic mechanism of the products with hierarchical structures was proposed. The obtained HDS-WO 3 exhibits excellent photocatalytic efficiency (84.9%), which is much higher than other WO 3 sample under visible light illumination. [ABSTRACT FROM AUTHOR]