Microscopic Characterization and Elemental Mapping of Catalytic Aerogels

Aerogels are good heterogeneous catalysts because of their high porosity, high specific surface area, and ability to maintain textural stability at high temperatures. One application of great interest of catalytic aerogels is found in their potential to replace the environmentally unfriendly three-way-catalysts (TWCs) employed in automobile catalytic converters. Characterization can provide information about aerogels’ nanostructure, including the distribution of atoms and availability of catalyst sites, and this can reveal ways to optimize catalytic efficiency. Scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) imaging were used to characterize copper-, cerium-, and nickel- containing silica and alumina catalytic aerogels made using the patented Union College rapid supercritical extraction (RSCE) method. Copper and cerium microparticles were identified, and clear images were obtained of ceria microcrystals.