Supercritical deposition is a promising way to prepare supported nanoparticles which have numerous applications in optics, electronics and catalysis. The technique involves the dissolution of an organometallic (OM) precursor in a supercritical fluid (SCF) and the exposure of a substrate to this solution. After adsorption of the precursor on the substrate, the metallic precursor is reduced to its metal form by various methods resulting in supported nanoparticles. Resorcionol-formaldehyde aerogels (RFAs) are precursors of carbon aerogels (CAs) and are promising candidates for catalysis applications. In this study, platinum nanoparticles supported on polymer RFA8 (with 8nm pore size) were synthesized. Effect of metal load on the average particle size of the supported nanoparticles was characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The particle size of the nanoparticles was ranged between 2 and 4nm depending on various platinum loadings (10wt%, 22wt.% and 34wt.%).Models consisting of equilibria or kinetics of adsorption of the OM to the support material are critical for design, operation and control of large scale SCF deposition technology for synthesis of supported nanoparticles. Therefore, the thermodynamics of adsorption of the platinum precursor dimetyhl (cyclooctadiene) platinum II (Pt(cod)me_2) on RFAs from supercritical carbon dioxide (scCO_2) was investigated using an experimental technique which consists of the direct analysis of the fluid phase.
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