title: Role of Exposed Surfaces on Zinc Oxide Nanostructures in the Catalytic Ethanol Transformation.
abstract: For a series of nanometric ZnO materials, the relationship between their morphological and surface functionalities and their catalytic properties in the selective decomposition of ethanol to yield acetaldehyde was explored. Six ZnO solids were prepared by a microemulsion-precipitation method and the thermal decomposition of different precursors and compared with a commercial sample. All these materials were characterized intensively by XRD and SEM to obtain their morphological specificities. Additionally, surface area determinations and IR spectroscopy were used to detect differences in the surface properties. The density of acid surface sites was determined quantitatively using an isopropanol dehydration test. Based on these characterization studies and on the results of the catalytic tests, it has been established that ZnO basal surfaces seem to be responsible for the production of ethylene as a minor product as well as for secondary reactions that yield acetyl acetate. Furthermore, one specific type of exposed hydroxyl groups appears to govern the surface catalytic properties.
authors.affiliation: Department Inorganic and Technical Chemistry, UNED, Facultad de Ciencias, Paseo Senda del Rey 9, 28040 Madrid (Spain).
authors.forename: María V
authors.initials: MV
authors.lastname: Morales
authors.affiliation: Department Inorganic and Technical Chemistry, UNED, Facultad de Ciencias, Paseo Senda del Rey 9, 28040 Madrid (Spain).
authors.forename: Esther
authors.initials: E
authors.lastname: Asedegbega-Nieto
authors.affiliation: Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain).
authors.forename: Ana
authors.initials: A
authors.lastname: Iglesias-Juez
authors.affiliation: Instituto de Catálisis y Petroleoquímica, CSIC, C/Marie Curie 2, Cantoblanco, 28049 Madrid (Spain).
authors.forename: Inmaculada
authors.initials: I
authors.lastname: Rodríguez-Ramos
authors.affiliation: Department Inorganic and Technical Chemistry, UNED, Facultad de Ciencias, Paseo Senda del Rey 9, 28040 Madrid (Spain). aguerrero@ccia.uned.es.
authors.forename: Antonio
authors.initials: A
authors.lastname: Guerrero-Ruiz
mesh_terms: D002384:Catalysis; D000431:Ethanol / Q000737:chemistry*; D008855:Microscopy, Electron, Scanning; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure; D017550:Spectroscopy, Fourier Transform Infrared; D013499:Surface Properties; D014961:X-Ray Diffraction; D015034:Zinc Oxide / Q000737:chemistry*
chemical_list: D000431:Ethanol; D015034:Zinc Oxide
keywords: acidity; biomass; dehydrogenation; surface analysis; zinc