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In situ anatase thin film with high percentage exposure of {001} facet was fabricated on titanium substrate via one-step hydrothermal method at low temperature from the precursor solution of (NH4)2TiF6 and HF. Nano-inverted bipyramid arrays densely covered the whole surface on as-treated Ti substrate. The structural analysis clearly indicated that as-deposited thin film only consisted of anatase TiO2 single crystal with preferred oriented {001} facets. According to the XRD patterns of as-treated anatase thin film, the integral intensity ratio of (004) to (101) peaks was as high as 7.5 which was remarkably higher than the standard value 0.18. Based on the experimental results, the growth pattern and bonding strength of nano-structural array with high percentage exposure of anatase {001} facet on Ti substrate were discussed. The biocompatibility results demonstrated that MC3T3-E1 cells grown on the as-treated Ti sheet exhibited positive effect on the cell proliferation and significantly high gene expression of ALP, COL-1, BMP-2, OPN and RUNX2 due to its specific property of the surface. Hence, the in situ anatase thin film with high percentage exposure of {001} facet was expected to achieve satisfactory primary stability for osseointegration. In situ fabrication of anatase TiO2 nano-inverted bipyramid arrays with high percentage exposure of {001} facet

Anatase/rutile dual layers were deposited on titanium and polyethylene substrates when they were soaked in TiOSO4/H2O2 solution and aged in hot water: The dense bottom layer predominantly consisted of rutile, while the upper layer consisted of loosely packed aggregation of anatase particles. The titania deposition was the results of compromise among three conflicting processes: (1) hydrolysis of TiOSO4 to yield either soluble titania-H2O2 complexes or titania, (2) dissolution of the titania layer under the presence of H2O2, and (3) corrosive reactions between titanium substrates and H2O2 to yield similar complexes or compounds. The dissolution–deposition equilibrium was found associated with pH of the sulfate solution and changed with soaking time. Thus, proper pH value and soaking time in the treating solution were the two key factors to control the formation of dense titania layers. The resulted titania layers were easily covered with fine apatite particles when soaked in a solution supersaturated with its component ions.

The alumina-titania catalysts were prepared from various alumina and titania sources by sol-gel method, which were metal alkoxide and metal alkoxide modified with organic groups. Specific surface area, pore size distribution, solid acidity and catalytic activity of NO reduction for the alumina-titania catalysts depended on the alumina and titania sources. The alumina-titania catalyst prepared from metal alkoxide for alumina source and metal alkoxide modified with organic groups for titania source exhibited higher activity of NO reduction than the other alumina-titania catalysts. Catalytic activity of NO reduction for the alumina-titania catalysts depended on specific surface area and solid acidity. It was suggested that solid acidity of the alumina-titania catalysts depended on the coordination structure of Al atoms and the homogeneity of alumina and titania components.

Organic precursors containing Al and Zr atoms were synthesized from an aluminium chelate compound and zirconium n-butoxide. A ZrO2-Al2O3 composite powder was prepared by the thermal decomposition of these precursors. An amorphous phase exists to higher temperatures for this ZrO2-Al2O3 powder than for a comparable powder prepared from aluminium sec-butoxide and zirconium n-butoxide. In addition the tetragonal ZrO2 phase was stabler in this ZrO2-Al2O3 powder than in a comparison powder. The ZrO2 grains were 50–500 nm in diameter and were homogeneously dispersed in the Al2O3 matrix after heating at 1400 °C.

The constitution of glasses in the systems M2O3-TeO2 (M = B and In) was investigated by Raman and infrared spectroscopy. From the relation between the M2O3 content and the intensity ratios of the deconvoluted Raman peaks I(720)/I(665) and I(780)/I(665), it was concluded that In2O3 behaves as a network modifier to yield TeO 3 − units and that discrete BO3 and BO4 units construct a network of glasses containing boron oxide. A structural model for those glasses was derived which involves three-coordinated oxygen atoms and TeO4 units of an intermediate configuration, O3Teδ+ ...Oδ-.

X-ray photoelectron spectra were measured of F 1s, O 1s, Pb 4f, and Si 2p core levels for lead fluorosilicate glasses of analysed compositions xPbF2·(69−x)PbO·(27–29)SiO2 (x

The mixture of a Zr-Al metallo-organic compound and Al2O3 powder yields dense ZrO2-Al2O3 composite ceramics. The fraction of the tetragonal ZrO2 phase in as-sintered ZrO2-Al2O3 ceramics is almost 100% and the ZrO2 grains at about 500 nm in diameter are dispersed in the matrix. The ceramics have high fracture toughness and bending strength.

ZrO2-Al2O3 composite powders have been prepared from a Zr-Al organometallic compound by thermal decomposition. X-ray diffraction patterns have indicated that the powders are amorphous below 800° C but tetragonal ZrO2 appears above 900° C and subsequently α-Al2O3and monoclinic ZrO2 appear above 1200°C. Transmission electron microscope analysis has shown that fine grains (5 to 20 nm in diameter) of ZrO2 are homogeneously dispersed in the ZrO2-Al2O3 composite particle and they grow in size with increase in the heating temperature. The measured lattice constants of α-Al2O3 phase have revealed that Zr atoms are practically insoluble (

Sialon powders have been prepared by heating mixtures of SiO2, Al2O3 2H2O and carbon in flowing nitrogen at 1470° C. The nitrogen content in the product powder increased with increasing added carbon, and was independent of both the flow rate of nitrogen gas and the surface area of pellet. The amount of SiO lost increased with an increase in the flow rate of nitrogen gas and surface area of the pellet and with a decrease in the amount of added carbon. A major part of the SiO evolved by the carbon reduction was trapped by carbon then consumed by carbon reduction and nitridation to form the sialon powder. The rest of the SiO was carried out of the system by the nitrogen gas. The amount of SiO lost and the nitrogen content can be estimated using the residual carbon content.

Calcium hydroxyapatite (Ca-HAP) ceramics containing tricalcium phosphate (TCP) were soaked in three solutions: phosphate buffer, tris buffer, and simulated body fluid (SBF). Petal-like crystals of Ca-HAP were deposited on the Ca-HAP ceramics when (i) Ca-HAP ceramics contained α-TCP, (ii) the soaking solution contained phosphate ion and (iii) the pH of soaking solution was higher than 7.3. These conditions facilitate the presence of HPO42−and Ca2+ ions, the latter from dissolution of α-TCP. A well-defined X-ray diffraction pattern for the deposited Ca-HAP crystals indicates preferred growth of {002} planes. Slower crystal growth of Ca-HAP was found for SBF (pH=7.5) than in the phosphate buffer, due possibly to the lower phosphate ion content in SBF.

Zr-Al organometallic compounds have been spray-dried and heated at temperatures 600 to 1400°C to prepare ZrO2-Al2O3 composite powders. The powders consist of balloon-like particles 0.5 to 2 μm in diameter with homogeneously dispersed tetragonal ZrO2 grains 0.1 to 0.2 μm in diameter. The tetragonal fraction of ZrO2 in the composite powders is higher than that in the powders prepared from sols of Zr(OBun)4 and Al[OCH(CH3)2]3. The fraction is affected by the organofunctional group in the Zr-Al compounds.