Synthesis and characterization of niobium oxide layers on silica and the interaction with nickel Original Research Article

A surface phase oxide containing niobiuma oxide, deposited on non-porous silica was prepared by two different methods. The photoelectron spectroscopy (XPS) and infrared results show that the method using five-stage attaching reactions between Nb(OC2O5)5 and silanol led to a very close one-atomic-layer niobium oxide structure on SiO2. This sample presented two oxygen species comparable to model systems and it was possible to distinguish them in the XPS spectral even when using a silica powder. Cyclohexane dehydrogenation was used to characterize the reduced metallic surface. The nickel compounds interact preferentially with niobia rather than with silica. These nickel species favored lower dehydrogenation activity, suggesting the choice of niobia as a nickel trap.