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Vanadium oxide thin films have been deposited on glass and ZnO-coated glass substrates by reactive RF-magnetron sputtering deposition at different substrate temperature. The introduction of ZnO buffer layer could increase the transmittance. The buffer layer ZnO could lead to the increase of the crystallinity quality of VO2 films and substrate temperature could be decreased to 100oC for the obtaining of polycrystalline VO2 structure. The structure of VO2/ZnO/glass is considered to be potentially applicable to ‘‘smart windows’’ of high total energy efficiency in architectures or automobiles. .

This paper describes a novel and simple method to preparing monoclinic VO2 (M) nanopowders via the reaction of ammonium meta-vanadate (NH4VO3) and oxalic acid dihydrate (C2H2O4•2H2O). The products were characterized by means of methods. XRD results show that well crystallized nanopowders of the monoclinic VO2 (M) were successfully synthesized, while the molar ratio between NH4VO3 and C2H2O4•2H2O was kept at 1:0.5~2.5, and the annealing temperature was 350~750 ℃ for 2~10 hour in nitrogen atmosphere. The spherical morphology of the samples is characterized by SEM. The crystallization temperature of the desired M/R-phase VO2 is lower than 387 ℃ in this work. And the phase transition temperature is determined by differential scanning calorimetry (DSC).

The aim of the study was to investigate the grafting process of β-cyclodextrin onto chitosan fibers via epichlorohydrin as a crosslinking agent. The parameters influencing the efficiency of the grafting reaction were studied by L9 (34) orthogonal test. The amounts of β-cyclodextrin grafting onto the treated fibers were estimated in terms of levofloxacin content. The optimum process was found to be epichlorohydrin 0.64 ml, temperature25℃, post-reaction time 48h, pre-reaction time 4.5h when chitosan fibers were 0.48g. In the case, the inclusion amount of levofloxacin was 1.792mg/g, and the releasing amount was 0.845mg/g at 35℃. The modified and unmodified fibers were characterized by FTIR Spectroscopy , which indicated that β-CD grafted with chitosan fibers were prepared successfully.

Vanadium dioxide (VO2) films were prepared on quartz glass and TiO2-coated quartz glass substrates by reactive RF-magnetron sputtering. The VO2 thin film with film thickness of 50 nm deposited on quartz glass substrates showed two kinds of regions with different color visible to the naked eye, i.e., the earth yellow region and the cyan region. Both XRD and Raman spectroscopy showed that the different color regions of the films had the different crystallinity quality and phase composition. Whereas, the VO2 thin films with film thickness of 50 nm fabricated on TiO2-coated quartz glass (with TiO2 film thickness of 50 nm) had uniform color and exhibited a larger change in transmittance at near infrared region than the VO2 thin films deposited on quartz glass did. A TiO2 buffer layer improved the crystallinity and uniformity of the VO2 film. Such very thin VO2 films with a TiO2 buffer layer have high potential for practical application in smart thermal glazing of windows.

A compact angle-resolved secondary ion mass spectrometer (AR-SIMS) with a special geometrical configuration, composing of a differentially pumped micro-beam ion-gun, a tiltable sample stage and a time-of-flight (TOF) mass spectrometer was applied to measure angular distribution (AD) of secondary ions ejected from VN by oblique 3 keV Ar+ sputtering at room temperature. AD of V+ was almost identical with that of N+, strongly suggesting that Gibbsian segregation did not take place during sputtering. Since the angular dependence of VN+/V+ and V2 +/V+ intensity ratios was independent of that of N+ and V+ intensities, VN+ and V2 + dimer ions were generated via the “as such” direct emission process.

Photochromic material Ag-TiO2 thin films are fabricated on quartz substrate by dual -target helicon magnetron sputtering. The phototchromic behavior is investigated for the sample loaded with 90% Ag. Spheres, ellipsoids and polyhedra shape of Ag particles with wide range size (5∼100 nm) are dispersed in the TiO2 amorphous matrix observed by transmission electron microscopy. The spectral hole burned by the irradiation of laser at the wavelength 532 nm can be explained by a particle-plasmon-assisted electron transfer from Ag nanoparticles to TiO2 and subsequent trapping by adsorbed molecular oxygen. Moreover, the mechanism of the slow recovery after photochromism is suggested as a slow thermal release of electrons from oxygen trapping centers and subsequent capture into the Ag nanoparticles.

We have prepared titania aerogel (=AG) embedded by NiB nano-clusters by sol-gel method, immersion of the prepared wet gel into the NiB dispersed solution, and the subsequent super critical drying (=SCD). The AG was characterized by X-ray diffraction (XRD), a transmission electron microscopy (TEM), and a fourier transform infrared spectrophotometer (FT-IR). XRD and selected area electron diffraction (SAED) patterns assured the formation of TiO2 anatase phase. TEM observation reveled the composition of TiO2 crystallites with about 4 nm in size. Catalyst performance for the ground sample was confirmed by chemical reaction of oxidation of benzene at low temperature, and the difference in catalyst performance between TiO2 AGs with and without the embedded NiB nano-clusters has been examined.

The photocatalytic effects of 4 samples, which TiO2 layer uniformly coated on Al fiber, are evaluated by NOx removal. An anatase TiO2 coating with good crystal quality and high Ti content exhibits the best photocatalytic effect on NOx removal. It is coincidence with the results of XRD, XPS results for 4 samples. The photocatalytic ability is enhanced by the introduction of H2O2 due to the formation of large amount OH radicals.