The Behavior of Flexible MIL-53(Al) upon CH4 and CO2 Adsorption

Anne Boutin (1) , François-Xavier Coudert (2, 3) , Marie-Anne Springuel-Huet (4) , Alexander V Neimark (5) , Gérard Ferey (6) , Alain Fuchs (2, 3)

1 PASTEUR - Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640)
2 ENSCP - Ecole Nationale Supérieure de Chimie de Paris - Chimie ParisTech-PSL
3 CNRS - Centre National de la Recherche Scientifique
4 LCMCP - Laboratoire de Chimie de la Matière Condensée de Paris
5 Rutgers University [Newark]
6 ILV - Institut Lavoisier de Versailles

The use of the osmotic thermodynamic model, combined with a series of methane and carbon dioxide gas adsorption experiments at various temperatures, has allowed shedding some new light on the fascinating phase behavior of flexible MIL-53(Al) metal−organic frameworks. A generic temperature-loading phase diagram has been derived; it is shown that the breathing effect in MIL-53 is a very general phenomenon, which should be observed in a limited temperature range regardless of the guest molecule. In addition, the previously proposed stress model for the structural transitions of MIL-53 is shown to be transferable from xenon to methane adsorption. The stress model also provides a theoretical framework for understanding the existence of lp/np phase mixtures at pressures close to the breathing transition pressure, without having to invoke an inhomogeneous distribution of the adsorbate in the porous sample.

Domaines: Chimie théorique et/ou physique; Matériaux

Anne Boutin, François-Xavier Coudert, Marie-Anne Springuel-Huet, Alexander V Neimark, Gérard Ferey, et al.. The Behavior of Flexible MIL-53(Al) upon CH4 and CO2 Adsorption. Journal of Physical Chemistry C, 2010, 114 (50), pp.22237-22244. ⟨10.1021/jp108710h⟩. ⟨hal-02310170⟩