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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.