Precipitation of micro and nanosilica and PdO/silica particles from SEDS technique using supercritical CO2

Abstract

This study utilized the Solution-Enhanced Dispersion by Supercritical Fluids (SEDS) technique to precipitate micro and nanosilica and PdO/silica composites using supercritical CO₂ as an anti-solvent and an ionic liquid as an adjuvant. Unlike previous studies, this work uniquely combines the sol-gel process with supercritical CO₂ technology, introducing ionic liquids to significantly enhance the surface area (up to 38-fold) and structural integrity of the silica particles. A detailed factorial experimental design was implemented to optimize key parameters such as temperature, CO₂ flow rate, and ionic liquid concentration, leading to the controlled synthesis of uniform nanoparticles and stable PdO/silica composites. The findings highlight the potential of this SEDS technique for advancements in materials science, catalysis, drug delivery, and environmental technology.