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Simultaneous NO _x and Particulate Matter Removal from Diesel Exhaust by Hierarchical Fe-Doped Ce-Zr Oxide.

ABSTRACT: Particulate matter and NO _x emissions from diesel exhaust remains one of the most pressing environmental problems. We explore the use of hierarchically ordered mixed Fe-Ce-Zr oxides for the simultaneous capture and oxidation of soot and reduction of NO _x by ammonia in a single step. The optimized material can effectively trap the model soot particles in its open macroporous structure and oxidize the soot below 400 °C while completely removing NO in the 285-420 °C range. Surface characterization and DFT calculations emphasize the defective nature of Fe-doped ceria. The isolated Fe ions and associated oxygen vacancies catalyze facile NO reduction to N₂. A mechanism for the reduction of NO with NH₃ on Fe-doped ceria is proposed involving adsorbed O₂. Such adsorbed O₂ species will also contribute to the oxidation of soot.

SUBMITTER: Cheng Y

PROVIDER: S-EPMC5460666 | biostudies-literature | 2017 Jun

REPOSITORIES: biostudies-literature

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Simultaneous NO x and Particulate Matter Removal from Diesel Exhaust by Hierarchical Fe-Doped Ce-Zr Oxide.

Cheng Ying Y Song Weiyu W Liu Jian J Zheng Huiling H Zhao Zhen Z Xu Chunming C Wei Yuechang Y Hensen Emiel J M EJM

ACS catalysis 20170426 6

Particulate matter and NO x emissions from diesel exhaust remains one of the most pressing environmental problems. We explore the use of hierarchically ordered mixed Fe-Ce-Zr oxides for the simultaneous capture and oxidation of soot and reduction of NO x by ammonia in a single step. The optimized material can effectively trap the model soot particles in its open macroporous structure and oxidize the soot below 400 °C while completely removing NO in the 285-420 ...[more]

PMID: 28603656

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