Nouveaux matériaux carbonés nanostructurés :
Application au stockage d'énergie,

Cathie Vix, Univ. de Mulhouse

The synthesis of porous carbon materials is a hot topic investigated in many laboratories since such materials are attractive for applications as diverse as gas separation, water purification, catalysts supports, hydrogen or methane storage, and many others. Synthesis pathways to create porous carbons are manifold and depend strongly on the characteristics of the carbons which are targeted. Using an exotemplating pathway, the synthesis of carbon materials with a high degree of control over their structural and textural properties can be achieved. This approach can be summarized as follows: First, the porosity of a 3D-connected ordered silica mesoporous material (e.g. SBA-15, MCM-48…) or a zeolite (e.g. NaY, FAU, EMT…) was filled with a carbon precursor. Various carbon precursors can be used such as propylene, sucrose, pitch, furfuryl alcohol, nitrogen containing precursors, etc. Second, the template was removed by an acid treatment. Thus, the carbon material which was formed inside the porosity of the template can be recovered. The resulting carbon materials were characterized at the atomic and mesoscopic scales using several techniques such as XRD, HRTEM, Raman spectroscopy, gas adsorption (N2, CO2), oxygen chemisorption (ASA). The surface chemistry of the carbons is studied by TPD and XPS. We showed that these characteristics are complex being not only related to the template but also to the carbon precursor and the way of impregnation. The synthesis in a confined geometry allows to obtain carbon materials with specific characteristics different from those encountered using a conventional synthesis way. The relation between the synthesis conditions of the materials and their final characteristics will be discussed in the presentation. These materials are especially attractive for energy storage applications.