MATOS, J.; SOUZA-FILHO, A.G.; BARROS, E.; RODRIGUEZ, J.A.; FERNÁNDEZ DE CÓRDOBA, M.C.; ANIA, C.O.:
Proceedings, 11th International Symposium on the Characterization of Porous Solids (COPS-XI) Avignon (France), May 2017, Page 53
Abstract
The synthesis of 2D and 3D porous carbon-based materials has been performed from the controlled pyrolysis of saccharose in the absence [1] or presence of KOH [2]. The topological properties of the bi-dimensional (2D) materials were significantly different from other 2D carbon-based cell structures. The pentagon was found to be the most abundant polygon in the films. In addition, three-dimensional (3D) irregular sponge balls were obtained with a similar topology than that of the films. XRD showed that graphite is the main crystalline phase; nevertheless, XPS showed important differences with respect to graphite. NEXAFS and RAMAN spectroscopy suggested the formation of graphene oxide [3]. In addition, the textural analysis (from gas adsorption and Hg porosimetry) pointed out the formation of a hierarchically pore structure in the present graphene-based materials.
One important application of these materials is in catalytic processes, due to their outstanding open pore network. In this sense, Fe-, Co- and Ni-doped carbon foams with catalytic activity were prepared using the methodology described above. These hybrid materials showed a remarkable development of the porous framework (compared to the non-metal doped carbon foams), and thus were studied in the dry methane reforming reaction under soft experimental conditions. The catalytic assays demonstrated that the metal-doped carbon foams were clearly more active and suffered less deactivation than bulk conventional catalysts prepared by wetness impregnation (using the same active metallic phase). It can be concluded then that the controlled pyrolysis of saccharides opens a new, low cost and eco-friendly method for the preparation of graphene-based catalytic membrane and membrane reactors from biomass wastes, mainly, polysaccharide fractions.