Accueil > Événements > Séminaires

Séminaire Chimie ED459

Acidic and basic sites at the surface of ordered mesoporous organosilicas

Dr. Barbara Onida (Department of Applied Science and Technology, Polytechnic of Turin, Torino, Italy)

publié le

Le Jeudi 14 Mars 2013 à 13h45
UM2, salle de cours SC-16.01

Ordered Mesoporous Organosilicas have attracted much attention in recent years, due to their hybrid composition which combines the chemical reactivity of organic moieties and the properties of the silica matrix. Besides Ordered Mesoporous Silicas (OMS) functionalized with organic moieties, which can be prepared either by one-pot co-condensation route or by post-synthesis modification, Periodic Mesoporous Organosilicas (PMO) may be included in this wide family of ordered mesoporous materials, being in this case the organic moieties part of the framework, though no silica domain actually exist in these systems.

Ordered Mesoporous Organosilicas are interesting for applications in heretogeneous catalysis, immobilization of functional molecules, such as dye, drugs or enzymes, and adsorption/separation. In all these fields, chemical properties of the surface, such as acidity, basicity, hydrophylicity and hydrophobicity, may play a crucial role.

In the present contribution, a study of acidic and basic sites at the surface of ordered mesoporous organosilicas is presented, which has been carried out by means of several spectroscopic techniques, such as IR, UV-visible, XPS, also investigating the adsorption of probe molecules. The study aims to elucidate the effect of the support on the reactivity of pendant acidic and basic groups (-COOH, -SO3H, -NH2) in both OMSs and PMOs and also how the hybrid nature of PMOs affect the acid-base properties of either Si-containing moieties and organic moieties in the framework.

Contact local ICGM : Dr. Yannick Guari (équipe CMOS)

Agenda

Ajouter un événement iCal