Adsorption of Precursors on Substrates in the Presence of scCO2 for the Synthesis of Supported Metallic Nanoparticles: Experiments and Modeling

Supercritical fluid reactive deposition is a promising technique for the synthesis of supported mono- or bimetallic nanoparticles. This process involves precursor dissolution in the supercritical fluid, adsorption of the precursor from the supercritical fluid mixture on the surface of the substrate and conversion of the precursor to its metallic form. Experimental results show, that the adsorption behavior of the precursor is the crucial process step that controls metal loading and the particle size. In this review, an overview on experimental and modeling work is given and experimental data were correlated with different adsorption isotherm models e.g. the Henry, Freundlich, Langmuir and Toth equation. Finally, strategies for overcoming current knowledge gaps and suggestions for future research are provided.