Synthesis, characterization and surface reactivity of tungsten carbide (WC) PVD films

Phase-pure tungsten carbide (WC) and Pt-modified WC thin films have been synthesized using the physical vapor deposition (PVD) technique. The physical and chemical properties of the PVD films have been studied using high-resolution electron energy loss spectroscopy (HREELS), X-ray photoelectron spectroscopy (XPS), temperature programmed desorption (TPD), and near edge X-ray adsorption fine structure (NEXAFS). TPD and HREELS have been utilized to investigate the reactivity of the WC and Pt-modified WC films toward the reaction with cyclohexene. The addition of Pt on the WC surface enhances the selective dehydrogenation pathway to produce gas phase benzene. The results reported here illustrate the feasibility of utilizing TPD and HREELS to investigate the surface chemistry of well-characterized PVD films.