Electron microscopy study on the Pd-Ce interaction in CeOx- Pd/alfa-Al2O3 catalysts for methane dry reforming

M.S. MORENO; F. WANG; M. MALAC; T. KASAMA; C.E. GIGOLA; I. COSTILLA; M.D. SÁNCHEZ

JOURNAL OF APPLIED PHYSICS

American Institute of Physics

Lugar: New York; Año: 2009 p. 105 - 110

0021-8979

Aclaración: Esta publicación resume parte de los resultados que obtuve en el trabajo desarrollado para mi tesis de Doctorado en Ingeniería Química, defendida el 27 de Marzo del 2012, y se encuentran publicados en los Capítulos 6 y 8 de la misma. Ademas, esta publicación fue seleccionada para la Virtual  Journal of Nanoscale Science and Technology, del American Institute of Physical Society, en su edicion del 4 de Mayo del año 2009.Abstract: We have investigated the interaction between Pd and Ce in a (0.47 wt %) CeOx?Pd(1  wt %)/alpha-Al2O3 catalyst that is used in the reforming reaction of CH4 with CO2. The freshly reduced catalyst was characterized by various electron microscopy techniques, such as elemental mapping, Z-contrast imaging, and electron energy-loss spectroscopy to understand the role of Ce on a microscopic scale. The high spatial resolution elemental mapping indicates that CeOx is located in close proximity of the palladium nanoparticles. High-resolution lattice images and energy-loss spectra obtained in the vicinity of the Pd particles show an anisotropic distribution of CeOx crystallites limited to the interface region between Pd and the substrate but not covering the surface of the Pd nanoparticles. Energy-loss near edge fine structure of Pd M edges reveals that the Pd nanoparticles are not oxidized.