The synthesis of precursors used in supercritical fluid deposition techniques and effect of precursors on particle morphology

In the thesis, new β-diketonate derivative ligand and metal complexes (precursors) have been prepared and used for Pd deposition on SBA-15 based silica, which can be used for supercritical carbon dioxide deposition technique. For this purpose, the acetylacetone compound is coupled with fluorine and fluorine-free alkyl groups having various chain lengths to the active methylene group and Pd (II) complexes of the ligands obtained are prepared. The structures of synthesized ligand and metal complexes were elucidated by analytical methods such as FT-IR, 1H, 19F NMR, elemental analysis, mass spectroscopy, magnetic susceptibility, UV-Vis. Their solubility in scCO2 and TGA analysis were tested to determine their suitability for supercritical CO2 deposition technique. Subsequently, Pd/SBA-15 nanoparticles were prepared by chemical reduction with hydrogen gas using supercritical CO2 deposition technique using synthesized precursors. The resulting metallic nanoparticles were analyzed by HR-TEM, BET, XRD and ICP-OES, contained 3.5-5.0% Pd and were found to have dimensions of 10-20 nm. The prepared Pd/SBA-15 nanocatalysts have been investigated for their catalytic activities in Suzuki-Miyaura cross-coupling reactions at different solvents and temperatures.