Controlling the growth of high-activity anatase TiO2 exposed {001} facets improves greatly the adsorption and electronic and photocatalytic properties and has been attractive for various environmental and energy-related applications. In this paper, we introduced a novel approach for quantitatively measuring the percentage of exposed {001} facets in anatase TiO2 by using Raman spectroscopy. Comparing to XRD, Raman peaks originate from the vibration of molecular bonds, that is, vibrational mode Eg and A1g peaks, which are related to different crystal planes. Therefore, it provided a high sensitivity and accuracy for measuring the percentage of the exposed facets from the micro perspective of molecular bonding with less measurement errors. With the photocatalytic experiments, we found that 50% was the optimal percentage of the exposed {001} facets for the highest efficiency, which seemed more reasonable than the value of 70% obtained from XRD.

The five-parameter Morse potential (5-MP for short) of interaction between adatom and metal cluster was constructed, and the adsorption of an O atom on Cu (100), Cu (110), Cu (111), Cu (211), and Cu (410) surfaces was studied by means of 5-MP. The data of the adsorption sites, adsorption geometry, binding energy, and eigenvibration, etc., for an O atom on the above surfaces are gained, and agree well with the experimental results. The diffusion of an O atom on plane surfaces is also dealt with. With regard to the adsorption of an O atom on the Cu (111) surface, calculation results suggest that the abnormally low experimental vibration of 29.4 meV of EELS (Dubois, L. H. Surf. Sci. 1982, 119, 399) arises from the effect of the sparse steps to the nearest neighbor 3-fold hollow site on the (111) terrace.

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