Coordination and organometallic chemistry applied to heterogeneous catalysis and materials science
Coordination chemistry with high denticity ligands and application to the preparation of inorganic materials
Research lines deal in general with the implementation of coordination and organometallic chemistry to the preparation of inorganic materials with functional properties and heterogeneous catalysts. These lines concern (1) the synthesis, spectroscopic and structural characterization of new coordination compounds based on Bi, Mo, V, Nb, Ta, and lanthanides, with high denticity ligands such as carboxylate, polyaminocarboxylate or peroxo(polyamino)carboxylate ligands. These compounds are adequate precursors for the preparation of oxide-type materials with appropriate morphological and textural properties, as bulk phases or thin films; (2) the search for new processes (non-classical precursors, sol-gel methods, hybrid precursors with organic polymers) for the preparation of heterogeneous catalysts based on Nb, V, Mo or pure and mixed Ni and Co molybdates modified by other elements. These catalysts are used essentially in alkane oxidative dehydrogenation.
Recent projects deal more specifically with the impact of the hydrophobicity-hydrophilicity balance on the textural and structural characteristics of solid catalysts, and the influence on these features on the catalytic performances. This concept is applied to the synthesis and use of mesoporous gallosilicates or related materials for the acetalization of glycerol to solketal (Collaboration with UNamur).
SEM images of (a,b) YVO4 and (c) GdVO4 prepared by various methods
Coordination chemistry of uranium in connection with the permanent geological disposal of nuclear waste in Boom clay
An additional research line concerns the mobility of uranium in Boom clay, which is considered as a natural barrier for potential geological disposal of nuclear waste in Belgium. All the factors concerning clay-radionuclide interactions have to be considered, and more specifically the interaction with the so-called “dissolved organic matter” (DOM), a polyfunctional matrix of very high complexity which is very heterogeneous both from the chemical and the viewpoint. The aim of this work is to investigate the influence of physical and chemical properties of Boom Clay DOM on its interaction with U(VI), and ultimately to perform a multiparametric study of U(VI)-DOM interaction processes and to derive the conditional thermodynamic constants of formed complexes or colloids (Collaboration with SCK-CEN, Mol and Helmholtz-Zentrum Dresden-Rossendorf).