Preparation and structure of alumina supported niobia model catalysts

Niobia/alumina model catalysts were prepared by physical vapor deposition of Nb in an oxygen atmosphere onto thin alumina films. Structural characterization, performed with scanning tunneling microscopy and infrared reflection absorption spectroscopy, revealed highly dispersed N2O5 nanoparticles exposing NbO groups. Thermal stability of the system was also examined. The results are compared with those obtained on thin niobia films and previously studied vanadia/alumina systems.