부산대학교 도서관

Abstract: The interaction of gallium with CeO2(111) layers was studied using standard and resonant photoelectron spectroscopy, by means of both a laboratory X-ray source and tunable synchrotron light. Firstly a 1.5-nm thick CeO2 film was grown on a Cu(111) substrate. Secondly Ga was deposited in six steps up to a thickness of 0.35nm, at room temperature. The interaction of gallium with the oxide layer induced partial CeO2 reduction, and gallium oxidation. The photoemission data suggest that a mixed Ga–Ce–O oxide was established similarly to the Sn–Ce–O case for Sn deposited on cerium oxide layers. As a consequence, gallium-induced weakening of Ce–O bonds provides a higher number of active sites on the surface that play a major role in its catalytic behaviour. [Copyright &y& Elsevier]