TiO2

Figure Bl.19.26. Highly resolved, non-eontaet AFM image of the TiO2(110)-(l x l) surfaee (8.5 x 8.5 imr)...

Fig. 2. UV-VISdiffiise reflectance sp>ectra of (a) TiO2-400°C, (b) CdS-IPA-800 C, (c) CdS-Ti02, (d) CdS-Ti02 physically mixed (PM).

The Raman spectra of WO3, 25-NiO-TiO2/30-WO3, 25-Ni0-Ti02/15-W03, 25- NiO-Ti02/5-W03, and Ti02 under ambient conditions are presented in Fig. 1. The WO3 structure is made up distorted WO3 octahedra. The major vibrational modes of WO3 are located at 808, 714, and 276 cm, and have been assigned to the W=0 stretching mode, the W=0 bending mode, and the W-O-W deformation mode, respectively [7]. The Raman spectrum of the 25-... 

The conventional sol-gel method was employed for the preparation of Ti02 and A1 (5.0- and 10.0-mol-%)-TiO2 catalysts. And these catalysts were characterized by XRD[model PW 1830 from Philips], SEM[model JEOL-JSM35CF], XPS[ESCA 2000], and TPD analyses for the elucidation of siuface phenomena. 

The tltanla-based thin film catalyst models were constructed by first oxidizing the titanium surface In 5 x 10 torr of O2 for approximately 30 minutes at 775 K. This produced an AES llneshape consistent with fully oxidized TIO2. The metal was then vapor deposited onto the oxide support with the latter held at 130 K. The thickness of the metal overlayer and Its cleanliness were verified by AES. After various annealing and adsorption procedures, these thin films were further characterized using SSIMS, AES and TDS. For comparison, some work was done with Pt on Al20s. In this case a Mo foil covered with AI2O3 replaced the Tl(OOOl) substrate. 

To explore the possibility of electronic Interaction between the reduced titanium oxide and Pt, 1 ML of Pt was deposited on both fully oxidized and partially reduced T102. The reduced sample was prepared by Ar" " sputtering of the TIO2 substrate prior to metal deposition. Introducing reduced Tl centers at the Pt-Tl Interface. 

Some results from this study of TIO2 surfaces were In good agreement with previous reports. For example, the C(372) peak could be removed by heating above 875K (20,21,23) Ar Ion bombard-... 

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