Homoepitaxy of the diamond thin films has been carried out by employing the ECR microwave plasma CVD apparatus with a CO/H2 gaseous source. From RHEED observation, it appeared that the surface morphology of (100) oriented film was much better than that of the (110) oriented. The (2×1) surface reconstruction remained unchanged even when the film was cooled down in H2 ambient after the epitaxy was completed. Although the synthetic diamond substrates had nonuniformity in their cathodoluminescence patterns, epitaxial films grown onto them offered uniform ones.

Visible-light-induced BiVO4-SiO2 composites photocatalysts with monoclinic scheelite structure were successfully synthesized via a sol-gel method, and were characterized with XRD, XPS, DRS, SEM and BET. The result indicated that BiVO4-SiO2 composite photocatalysts exhibited relatively high BET surface areas, consisting of primary nanocrystals with average size of 44 nm. The band gap of the sample was estimated to be 2.56 eV, representing an obvious blue-shift compared with that of the SSR-BiVO4 sample. The photocatalytic activities were also evaluated by decolorization of methylene blue (MB) under blue light. The photodegradation rate of BiVO4-SiO2 composite photocatalysts was quite high, up to 69% in 2 h, which was much better than that of the reference sample prepared by solid-state reaction (5.5%) under the same conditions.

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We review theoretical treatments of physisorption of Xe on Cu(111) and Pt (111) surfaces within the recently proposed extended density functional approach that explicitly takes into account the van der Waals interactions among the constituents of adsorption systems. Based on tests of the various currently used approximations for the density functionals, and of the different treatments of long-range correlation effects which we carried out for a prototype system of a Kr dimer, we have adopted in the present study the schemes that are appropriate to systems consisting of nearly isolated fragments. In this approach the coefficients of van der Waals expansion are deduced from the DFT calculations of intrafragment electronic densities. Such generalized DFT calculations of potential energy surfaces yield a structure of Xe adlayers in good agreement with experiments and retrieve the dilation of the commensurate monolayer phase with strongly reduced intralayer Xe-Xe radial force constants. This approach provides a first principles interpretation of the observed vibrational properties of commensurate adlayers of Xe physisorbed on Cu(111) and Pt (111) surfaces.

Alumina/carbon nanotubes (Al2O3/CNTs) composite coating was synthesized by plasma spray employing mixtures of Al2O3-coated CNTs and nano-sized α-Al2O3 at atmosphere. This coating was characterized for the microstructure and the composition by X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS), high resolution transmission electron microscopy (HRTEM), thermo gravimetric analysis (TG), differential scanning calorimetry analysis (DSC) and scanning electron microscopy (SEM). The results show that the thickness of the coating is about 0.5mm and the constituent elements were changed to α-Al2O3, CNTs and γ-Al2O3 duo to the superhigh temperature during the plasma spray process. The great mass of the mixtures were melted well and the CNTs were dispersed uniformly in the melted ceramic. The oxidation resistance and the microwave absorption properties were discussed simply to describe the functions of the composite coating.