An HREELS investigation of MnOx/Rh(100) model catalyst

The structure and physical chemical properties of the MnOx/Rh(100) model catalysts, as well as O/Rh(100), have been investigated in this work using high-resolution electron energy loss spectroscopy (HREELS), low-energy electron diffraction (LEED), and Auger electron spectroscopy (AES) techniques. The results show that the oxidation of the Rh(100) surface leads to form a trilayer O-Rh-O surface oxide. The MnOx grows in a layer-by-layer mode on the Rh(100) surface, and forms an O-Mn-O-like trilayer structure as evidenced by the HREELS phonon features. The MnOx with sub-monolayer coverage is stable on the Rh(100) surface. The HREELS phonon features with peaks at 68 and 83 meV indicate that Mn3O4 structure forms at higher overage. The Mn3O4 structure was found to be stable by annealing at 800 K. (C) 2015 Elsevier B.V. All rights reserved.