Highly ordered TiO2 nanotube array (TN) films were prepared by anodization of titanium foil in a mixed electrolyte solution of glycerin and NH4F and then annealed at 200°C, 400°C, 600°C, and 800°C, respectively. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), water contact angle (WCA), and photoluminescence (PL). It was found that low temperature (...

We studied the structural behavior and electrical transport properties of epitaxial a-SnO thin films grown on the (1̄012) a-Al2O3 ~sapphire! substrate. Hall effect measurements revealed that the epitaxial as-deposited SnO film is a p-type semiconductor. In situ x-ray diffraction studies show that the a-SnO phase is metastable and will transform into SnO2 with the rutile type structure when annea...

The most widely used oxide for photocatalytic applications owing to its low cost and high activity is TiO2. The discovery of the photolysis of water on the surface of TiO2 in 19721 launched four decades of intensive research into the underlying chemical and physical processes involved2–5. Despite much collected evidence, a thoroughly convincing explanation of why mixed-phase samples of anatase ...

Unique nanorod-like mesocrystals constructed from ultrathin rutile TiO2 nanowires were successfully fabricated for the first time using a low-temperature additive-free synthetic route, and the mesocrystal formation requirements and mechanism in the absence of polymer additives were discussed. The ultrathin nanowires were highly crystalline and their diameters were found to be ca. 3–5 nm. The ru...

Titanium dioxide (TiO2) nanoparticles were prepared by the sol-gel method at different pH values (3.2-6.8) with a hydrochloric acid (HCl) solution. Raw samples were calcined at 500 °C for 2 h. The effects of pH on the structural, morphological and optical properties of TiO2 nanoparticles were investigated. At pH 4.4-6.8, only the anatase phase of TiO2 was observed. Under strong acidic condition...

Anatase-to-rutile phase transformation was studied in milled and unmilled samples. Ball milling was carried out in two types of ball mills, planetary and tumbler, with a ball-to-powder ratio of 40:1 over 2-48 hours. First, the unmilled samples were heated in the furnace at various temperatures for different periods of time. The results revealed that the anatase-to-rutile transformation comple...

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...

TiO2-based nanofibers were synthesized using a sol-gel method and electrospinning technique. The as-spun composite fibers were heat-treated at different temperatures (500°C, 550°C, 600°C, and 650°C) and atmospheres (ammonia and nitrogen) for 4 h. The fibers had diameters of 50 to 200 nm and mainly featured anatase and rutile phases. The anatase phase decreased and the rutile phase increased wit...

The mechanism of lithium insertion that occurs in an iron oxyfluoride sample with a hexagonal-tungsten-bronze (HTB)-type structure was investigated by the pair distribution function. This study reveals that upon lithiation, the HTB framework collapses to yield disordered rutile and rock salt phases followed by a conversion reaction of the fluoride phase toward lithium fluoride and nanometer-siz...

Anatase/rutile mixed titania nanotubes (TiO2 NTs) precipitated with gold nanoparticles (Au NPs), i.e. Au/TiO2, have been synthesized and investigated on visible photocatalysis properties. A deposition-precipitation (DP) method was adopted to reduce the gold precursor to Au NPs within the preformed TiO2 NTs by the emulsion electrospinning technique. The optimal visible photocatalytic activity wa...