Posted: February 6, 2009

Researchers synthesize new generation of tri-purpose nanocatalysts for reduced exhaust emissions

(Nanowerk News) Researchers at the University of Tehran synthesized a new generation of tri-purposed nano-catalysts, which are an important development in reducing automotive exhaust gas emissions (Pd-doped LaCoO3 regenerative catalyst for automotive emissions control).
“Conventional exhaust catalysts are loaded with excess amounts of precious metals such as platinum, palladium and rhodium for treatment of pollutants," said Sina Sartipi, who carried out the research.
"We decided to observe the effect of partial substitution of cobalt by Palladium in LaCoO3 perovskite structure (doping) and check if it can be used as an appropriate alternative component for conventional catalysts," he added.
Asked about the catalyst’s behavior, Sartipi said that palladium nano-particles might diffuse into the perovskite lattice in oxide form. In reducing atmospheres, they segregate out and disperse as metallic nanoparticles on the surface of perovskites.
There is a reversible transfer between active surface area and volume of the regenerative catalyst. The environment of automotive exhaust gas fluctuates between oxidative and reductive atmospheres. Therefore, the catalyst adapts its structure to the environmental redox fluctuations as a reversible response. That is why such regenerative converters are also called Smart Catalysts.
The most significant advantage of this product, compared to similar catalytic converters, would be its high activity leading to a longer life and more efficient functioning of gasoline engines. We plan to introduce the technology to the industry.”
The project was conducted under the guidance of Dr. Abbas Ali Khodadadi, Dr. Yadollah Mortazavi, in Catalysis and Nanostructured Materials Research Laboratory, School of Chemical Engineering, University of Tehran.
Source: Iranian Nanotechnology Initiative