Investigation of ceria-nickel-containing aerogels for catalytic converter applications

Aerogels are solid materials that have physical properties that make them appealing for automotive exhaust catalysis: they are highly porous with low density and high surface area. The goal of a catalytic converter is to reduce the emitted level of poisonous gases such as CO and NOx by converting those to less harmful gases. Current catalytic converter technology uses expensive metals such as platinum, palladium, and rhodium. So, catalytic metal-containing aerogel can potentially be a less expensive alternative for use in catalytic converters. Ceria- nickel-containing aerogels show promising results from previous experiments. Ceria (cerium oxide) can undergo a rapid change in oxidation state and nickel aerogels have shown redox potential. The change in oxidation state in ceria aerogels is important in oxygen storage for redox reactions that take place in the catalytic converter. Having two different types of catalytic metals in an aerogel can potentially improve the catalytic properties as opposed to aerogels with only one type of catalytic metal. The ceria-nickel-containing aerogels are fabricated using the rapid supercritical extraction method patented by Union College, and the catalytic testing is performed using the Union College Catalytic Aerogel Testbed, designed and built by Union College faculty and students. This presentation will describe the preparation and characterization of these novel materials.