Textural evolution (porosity reduction, pore and crystallite growth) in titania-alumina composite membranes has been studied using thermal analysis, X-ray diffraction, field emission scanning electron microscopy and N, physisorption techniques. The presence of alumina in the membranes improved the thermal stability of the porous texture by retarding the anatase-to-rutile phase transformation a...

monometallic and bimetallic ni and co catalytic nanoparticles supported on titanium dioxide (rutile phase) substrate were prepared by wet impregnation method. these nanoparicles were used as catalysts for synthesis of multiwalled carbon nanotubes (mwcnts) from acetylene decomposition at 700°c by the catalytic chemical vapor deposition (ccvd) technique. the nanomaterials (catalyst and cnts) were...

nano-sized titanium dioxide tio2 powder was prepared by new wet chemical route from its precursor titanium (iv) chloride (ticl4) as precursor with isopropoxy alcohol in presence of nitric acid under ambient condition. their morphologies, phase compositions and components of the tio2 nanoparticles were characterized by transmission electron microscopy (tem), field emission scanning electron micr...

The paper deals with application of three nanomaterial systems: undoped TiO2, chromium-doped TiO2:Cr and TiO2-SnO2 synthesized by flame spray synthesis (FSS) technique for hydrogen sensing. The emphasis is put on the role of anatase and rutile polymorphic forms of TiO2 in enhancing sensitivity towards reducing gases. Anatase-to-rutile transformation is achieved by annealing of undoped TiO2 in a...

Titania is the most widely studied photocatalyst. In its mixed-phase configuration ( anatase–rutile form) – as manifested in the commercially available P25 Degussa material – titania was previously found to exhibit the best photocatalytic properties reported for the pure system. A great deal of published research by various workers in the field has not fully explained the underlying mechanism f...

With ethanol as a probe molecule, the surface sites of anatase and rutile can be distinguished using (13)C CP/MAS NMR spectroscopy, which offers an opportunity to investigate the transfer of photo-induced electrons from rutile to anatase in the mixed-phase TiO2.

Co-doped TiO2 nanoparticles containing 0.0085, 0.017, 0.0255, 0.034, and 0.085 mol % Co(III) ion dopant were synthesized via sol-gel and dip-coating techniques. The effects of metal ion doping on the transformation of anatase to the rutile phase have been investigated. Several analytical tools, such as X-ray diffraction (XRD), transmission electron microscope (TEM), X-ray photoelectron spectros...

In this study, we focused on the origin on the selective deposition of rutile and anatase TiO2 thin films during the sputtering process. The observation on microstructural evolution of the TiO2 films by transmission electron microscopy revealed the coexistence of rutile and anatase TiO2 phases in the initial stage under the preferential growth conditions for the anatase TiO2; the observations f...

Recent breakthrough of novel hierarchic materials, orchestrated through oriented attachment of crystal subunits, opened questions on what is the mechanism of their self-assembly. Using rutile-type TiO2, synthesized by hydrothermal reaction of Ti(IV)-butoxide in highly acidic aqueous medium, we uncovered the key processes controlling this nonclassical crystallization process. Formation of comple...