New catalytic converter for cleaner city air

Berlin: Scientists have designed a dynamic catalytic converter for vehicles that can efficiently treat exhaust gases to ensure cleaner air in the cities. Thanks to its good catalytic properties, platinum is often applied in catalytic converters of vehicles, researchers said. The new converter is based on the interaction between platinum and cerium oxide carrier to control catalytic activity by short-term changes of the engine’s operation mode, they said. Scientists from Karlsruhe Institute of Technology (KIT) in Germany used a diesel oxidation catalytic converter (DOC), in which afterburning of hydrocarbons and carbon monoxide takes place. They found that the particle size and oxidation state of the platinum component during operation can be modified specifically. Interactions between the carrier material and the applied noble metal play an important role. The results reflect a highly dynamic catalytic converter surface that reacts extremely sensitively to external impacts, such as exhaust gas composition. “The special thing is that we can adjust the size and state of the noble metal nanoparticles on the surface of the catalytic converter,” said Andreas Ganzler, from KIT’s Institute for Chemical Technology and Polymer Chemistry (ITCP). “The methods enable us to do this under relevant and even real operation conditions and, hence, to directly adjust the catalytic activity of materials,” said Ganzler, lead author of the study published in the journal Angewandte Chemie.