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A nearly 100% filling of PEDOT in TiO 2 nanotube array (NTA) was successfully prepared by a simple electropolymerization method at a constant potential of 1.8 V, which was demonstrated by field emission scanning electron microscopy (FESEM). UV–vis diffusion reflection spectroscopy (DRS) revealed that the filling of PEDOT in TiO 2 NTA can dramatically improve the visible-light and near-infra-red absorption property of the TiO 2 NTA, which is especially useful for the application of solar cells. Cyclic voltammetry experiments indicate that the PEDOT–TiO 2 NTA hybrid material is electrochemically more active than the TiO 2 NTA and has excellent redox reversibility. [ABSTRACT FROM AUTHOR]

Abstract: The Ag and CdS nanoparticles co-sensitization of TiO2 nanotubes (CdS–Ag/TiO2 NTs) were prepared by successive ionic layer adsorption and reaction (SILAR) technique. The phase composition, morphology and optical property were characterized by the X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis diffusion reflection spectroscopy (DRS). The co-modification of Ag and CdS nanoparticles expanded the photoresponse range of TiO2 NTs from ultraviolet region to 668.7nm, and the CdS–Ag/TiO2 NTs prepared by SILAR deposition of 5 cycles exhibited higher visible photocurrent and stability against photocorrosion. The detailed electrons transfer mechanism of CdS–Ag/TiO2 NTs was proposed, and photocatalytic activity toward degradation of methyl orange (MO) under visible-light irradiation was also investigated. [Copyright &y& Elsevier]

Abstract: Ordered anatase TiO2 nanotubes (TiO2 NTs) on Ti substrate were synthesized by electrochemical anodization and subsequently vapor-thermal treatment. Ag nanoparticles were decorated on TiO2 NTs by successive ionic layer adsorption and reaction (SILAR) technique. Raman spectroscopy, X-ray absorption near edge spectroscopy (XANES), X-ray diffraction (XRD), UV–vis diffuse reflectance spectroscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used for the characterization of surface morphology, phase composition, and microstructure of the original TiO2 NTs, the vapor-thermally treated TiO2 NTs and the Ag nanoparticles decorated TiO2 NTs. The results indicate that vapor-thermal treatment favors to the transformation of amorphous TiO2 into anatase phase. Increasing the SILAR cycle times favors to increase the loaded amounts of Ag nanoparticles in TiO2 NTs. Ag nanoparticles are uniformly distributed in the TiO2 NTs, and the SILAR process does not damage the ordered tubular structure. A possible formation mechanism of Ag/TiO2 NTs has also been proposed. The photocatalytic results showed that the Ag nanoparticle modified TiO2 NTs largely enhanced the photocatalytic degradation of methyl orange under ultraviolet light irradiation. [Copyright &y& Elsevier]

Abstract: Nitrogen-doped titanium dioxide mesosponge was fabricated by transformation of TiO2 nanotube arrays using a facial solvothermal method. The structure, morphology and optical property were investigated by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–vis diffusion reflection spectroscopy (DRS). A possible formation mechanism of N-doped TiO2 mesosponge has been proposed. The photoelectrochemical results indicate that N-doped TiO2 mesosponge prepared in ethanol solution of ammonia exhibits much higher photocurrent densities and the optimal photocatalytic activity. [Copyright &y& Elsevier]

Abstract: Anatase titanium dioxide (TiO2) mesoporous microspheres with core–shell and hollow structure were successfully prepared on a large scale by a one-step template-free chemical vapor deposition method. The effects of various reaction conditions on the morphology, composition and structure of the products were investigated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer–Emmett–Teller (BET) technique and photoluminescence (PL) method. The results indicate that the product near the source was composed of core–shell structure TiO2 microspheres with diameters from 3 to 5μm. With increasing the distance between the source materials and the substrate, the hollow TiO2 spheres with 1–2μm dominant the products. A localized Ostwald ripening can be use to explain the formation of core–shell and hollow structures, and the size of the initial TiO2 solid nanoparticles plays an important role in determining the evacuation manner of the solid in the ripening-induced hollowing process. The surface area of TiO2 hollow microspheres determined by the adsorption isotherms was measured to be 74.67m2/g. X-ray photoelectron spectroscopy (XPS) analysis revealed that the O–H peaks of hollow structures have a chemical shift compared with the core–shell structures. The optical property of the products was also discussed. [Copyright &y& Elsevier]