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Electrorheological (ER) polishing is a novel polishing technology having flexible and tunable characteristics. At present, ER polishing uses ER particles to drive abrasive particles to polish the material surface. Under the action of high-speed centrifugation, the abrasive particles are easily separated from ER particles due to their significantly different ER effect, and this can easily cause the degradation of polishing ability. In this work, alumina-doped titanium dioxide ER polishing particles were developed via a sol-gel method. As a classical abrasive, alumina has higher hardness and can improve the ER effect of titanium dioxide by doping. Thus, alumina-doped titanium dioxide particles simultaneously possess high ER effect and high hardness. No phase separation appears in the polishing process and the result shows that alumina-doped titanium dioxide has a good polishing efficiency for materials with Mohs hardness of 3 and below. [ABSTRACT FROM AUTHOR]

Electric field-induced particle polarization is essential to the electro-responsive electrorheological (ER) effect of particle suspensions. In this work, we use graphene oxide (GO) as a soft and polar coating shell to prepare GO-wrapped titania dielectric microspheres for use as the dispersal phase of an ER suspension. Under a DC electric field, the ER characteristic of GO-wrapped titania microspheres dispersed in silicone oil is investigated by rheological tests, and then compared with that of a suspension of bare titania microspheres. The results show that the suspension of GO-wrapped titania microspheres possesses an enhanced ER characteristic. Its field-induced shear yield stress and storage modulus are much higher than those of the suspension of bare titania microspheres. The soft and polar GO shell is regarded as the origin of the ER enhancement. Dielectric analysis indicates that wrapping GO can enhance the interfacial polarization and thus improve the ER characteristics of titania microspheres. Wrapping GO onto the surface of titania microspheres can also reduce the particle sedimentation velocity of the suspension. [ABSTRACT FROM AUTHOR]

Abstract: This paper reports the synthesis of AgInS2 cluster films on TiO2/FTO substrate by the hydrothermal route and demonstrates the photoelectric application of them. The AgInS2 clusters with an average particle size of 0.8µm were synthesized on the surface of TiO2 nanorod arrays. The investigation results of photoelectric performance indicate that the fill factor of AgInS2 clusters/TiO2 nanorod array photoelectrode is 65.8%, and the energy conversion efficiency is 1.039%, which is twice that of bare TiO2 nanorod array photoelectrode. [Copyright &y& Elsevier]

This article reported a well-organized 3D urchin-like hierarchical TiO2 which was synthesized by a simple solvothermal method without using any template or surfactant. The results of scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, and powder X-ray diffraction showed that the hierarchical morphology and size of TiO2 could be effectively controlled by adjusting the precursor ratio of tetrabutyl titanate to TiCl4solution, the concentration of TiCl4 solution, the solvothermal temperature, and the reaction time. It is believed that the formation of the urchin-like hierarchical TiO2 followed a 'nucleation-self-assembly-dissolution-recrystallization' growth mechanism. In addition, the excellent photocatalytic activity of the urchin-like hierarchical TiO2 was confirmed by photodegradation of methyl blue in water. [ABSTRACT FROM AUTHOR]

We report a facile method to grow multi-sectional TiO2 nanotube arrays consisting of alternating bamboo-shaped and smooth-walled nanotube sections by anodization. Two key factors are necessary for obtaining these morphologies. First, in order to avoid possible disruptions between the conjoint sections of the nanotube, the distribution of hydrogen ions is suggested not to be fiercely disturbed when switching from the first to the second stage. Second, to avoid the disruption of the nanotube at the joint which results from the disparity in diameters between sections, the direct current voltage is set to be the maximum of the square wave voltage. These newly developed TiO2 nanotube arrays are expected to have potential applications in solar cells, drug release and delivery systems. [ABSTRACT FROM AUTHOR]

Abstract: Titania (TiO2) spheres were fabricated by a solvent evaporation process in which anhydrous ethanol was used as the only solvent. This is a simple and novel route for the fabrication of TiO2 spheres. The spheres have a narrow particle size distribution and an average diameter of approximately 1.0 µm. The crystal structure of the prepared spheres was improved by high-temperature processing. A possible mechanism for the formation and growth of the spheres is proposed in which titanic acid molecules react with each other through hydroxyl condensation to form primary TiO2 particles. These aggregate and increase in size by surface reaction, and finally form spheres. [Copyright &y& Elsevier]

Two kinds of hierarchical anatase TiO 2 structures are synthesized by a facile hydrothermal method in this report. A new transparent, 3D light-collected, and flexible fiber-type dye-sensitized solar cell (FF-DSSC) with such hierarchical TiO 2 structures is developed. The conversion efficiency of the FF-DSSC based on a TiCl 4 -treated TiO 2 nanorod array (hierarchical structure I) exhibits about 4 times higher than that based on a HCl-treated TiO 2 nanorod array, and further rises to 4.4% when the TiCl 4 -treated TiO 2 nanorod array is treated in a mixed solution of (NH 4 ) 2 TiF 6 and H 3 BO 3 three times (hierarchical structure II). The obvious enhancement in conversion efficiency can be ascribed to the dye adsorption promotion benefiting from their hierarchical structures. Beyond the attractive conversion efficiency, the new designed FF-DSSC possesses several advantages including good flexibility, excellent stability, and 3D light-collection. The conversion efficiencies of the FF-DSSCs can still keep 85%–90% even the FF-DSSCs are bent for 1000 times. The maximum power outputs of the FF-DSSCs characterized by Diffuse Illumination Mode using home-made Al reflector exhibit about 3 times higher than that done by Standard Illumination Mode due to 3D light-collections. The FF-DSSCs based on highly ordered hierarchical anatase TiO 2 nanorod arrays hold great promise in future energy harvest. [ABSTRACT FROM AUTHOR]

Highlights: [•] Au or Ag nanoparticle-decorated 3D urchin-like TiO2 nanostructures were prepared. [•] The decorated nanostructures show quenched photoluminence. [•] The decorated nanostructures exhibit superior photocatalytic activity. [ABSTRACT FROM AUTHOR]

Abstract: Arrays of TiO2 nanotubes were fabricated by the anodization of Ti foils and then used in assembling dye-sensitized solar cells (DSSCs). The role of the morphologies of the TiO2 nanotubes in the photovoltaic performances of the DSSCs was studied in terms of the surface topography and the tube length. The necessity of removing the nanoporous films from the surface of the nanotube arrays for good DSSC performance has been demonstrated. Also, it has been shown that appropriately increasing the tube length was an effective measure for enhancing both the short-circuit current density and the conversion efficiency of the DSSCs. [Copyright &y& Elsevier]