Infrared Spectroscopy Investigation of the Acid Sites in the Metal-Organic Framework Aluminum Trimesate MIL-100(Al) - CNRS - Centre national de la recherche scientifique Accéder directement au contenu
Article Dans Une Revue Journal of Physical Chemistry C Année : 2012

Infrared Spectroscopy Investigation of the Acid Sites in the Metal-Organic Framework Aluminum Trimesate MIL-100(Al)

Résumé

Infrared spectra of MIL-100(Al) have been recorded after evacuation from room temperature up to 623 K. In addition to adsorbed water molecules characterized by specific (nu+delta)H2O combination bands at about 5300 cm(-1), spectra analysis shows the presence of impurities like carboxylic acid and nitrates resulting from the synthesis step, explaining the low amount of Al-OH groups detected. The Lewis acidity has been characterized by CO [nu(CO) at 2183 cm(-1), pyridine [nu 8a band estimated at 1618 cm(-1)], and CD3CN [nu(CM) at 2326 cm(-1)] adsorption on the activated sample. The acidity is strong as revealed by the nu(CN) wavenumber. Interestingly, CO gives rise to an interaction weaker than that expected from pyridine and CD3CN results. Quantitative results relative to the number of Al-5c(3), sites are in full agreement with those reported elsewhere from Al-27 NMR experiments. The Bronsted acidity mainly results from the presence of coordinated water species in the nonfully dehydrated sample and not from the structural Al-OH groups.

Domaines

Chimie
Fichier non déposé

Dates et versions

hal-01840365 , version 1 (16-07-2018)

Identifiants

  • HAL Id : hal-01840365 , version 1

Citer

Christophe Volkringer, Herve Leclerc, Jean-Claude Lavalley, Thierry Loiseau, Gerard Ferey, et al.. Infrared Spectroscopy Investigation of the Acid Sites in the Metal-Organic Framework Aluminum Trimesate MIL-100(Al). Journal of Physical Chemistry C, 2012, 116 (9), pp.5710--5719. ⟨hal-01840365⟩
250 Consultations
0 Téléchargements

Partager

Gmail Facebook X LinkedIn More