NON-COVALENT IMMOBILIZATION OF N/S/P-DONOR 3d-METAL COMPLEXES ON SILICA GEL: A PROPOSED STRATEGY FOR FUNCTIONAL HETEROGENEOUS MATERIALS
Keywords:
silica gel; 3d metals; N/S/P-donor ligands; non-covalent immobilization; coordination complexes; adsorption; heterogeneous catalysis; FTIR; BET.Abstract
This thesis presents a scientific and methodological strategy for the formation of first-row 3d-metal complexes with nitrogen-, sulfur- and phosphorus-donor ligands and their non-covalent immobilization on a porous silica-gel matrix. The central concept is to preserve the coordination environment of the preformed metal–ligand complex while dispersing it over the SiO₂ surface through physical adsorption, hydrogen bonding, electrostatic, dispersive and donor–acceptor interactions. Fe, Co, Ni, Cu and Zn are considered as representative 3d metals. A stepwise procedure is proposed, including silica activation, complex formation, contact with silica gel, washing, drying and instrumental characterization. FTIR, UV–Vis/diffuse reflectance, XRD, SEM–EDS, BET and TGA/DTG are identified as complementary methods for assessing surface interactions, elemental distribution, porosity and thermal behavior. The approach may provide a practical platform for reusable heterogeneous catalysts and functional sorbents. Because the source study is a conceptual experimental model, numerical performance parameters are not presented as measured results and should be established by laboratory experiments.
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