Local structure of Iridium organometallic catalysts covalently bonded to carbon nanotubes

Blasco, Javier (Universidad de Zaragoza) ; Cuartero, Vera ; Subías, Gloria (Universidad de Zaragoza) ; Jiménez, M. Victoria (Universidad de Zaragoza) ; Pérez-Torrente, Jesús J. (Universidad de Zaragoza) ; Oro, Luis A. (Universidad de Zaragoza) ; Blanco, Matías ; Älvarez, Patricia ; Blanco, Clara ; Menéndez, rosa

Resumen: Hybrid catalysts based on Iridium N-heterocyclic carbenes anchored to carbon nanotubes (CNT) have been studied by XAFS spectroscopy. Oxidation of CNT yields a large amount of functional groups, mainly hydroxyl groups at the walls and carboxylic groups at the tips, defects and edges. Different kinds of esterification reactions were performed to functionalize oxidized CNT with imidazolium salts. Then, the resulting products were reacted with an Ir organometallic compound to form hybrid catalysts efficient in hydrogen transfer processes. XANES spectroscopy agree with the presence of Ir(I) in these catalysts and the EXAFS spectra detected differences in the local structure of Ir atoms between the initial Ir organometallic compound and the Ir complexes anchored to the CNT. Our results confirm that the halide atom, present in the Ir precursor, was replaced by oxygen from -OH groups at the CNT wall in the first coordination shell of Ir. The lability of this group accounts for the good recyclability and the good efficiency shown by these hybrid catalysts.

Idioma: Inglés

DOI: 10.1088/1742-6596/712/1/012052

Año: 2016

Publicado en: Journal of Physics: Conference Series 712, 012052 (2016), [5 pp.]
ISSN: 1742-6588

Factor impacto SCIMAGO: 0.24 - Physics and Astronomy (miscellaneous) (Q3)

Financiación: info:eu-repo/grantAgreement/ES/DGA/E07
Financiación: info:eu-repo/grantAgreement/ES/DGA/E69
Financiación: info:eu-repo/grantAgreement/ES/MINECO-FEDER/CTQ2010-15221
Financiación: info:eu-repo/grantAgreement/ES/MINECO/MAT2012-38213-C02-01

Tipo y forma: Article (Published version)

Área (Departamento): Área Química Inorgánica (Dpto. Química Inorgánica)
Área (Departamento): Área Física Materia Condensada (Dpto. Física Materia Condensa.)