Abstract: NO_x storage-reduction (NSR) is one of the most promising techniques for lean NO_x abatement. The periodical lean/rich conditions and the combination of the stoichiometric reaction and the catalytic reaction on NSR catalyst distinguish the NSR catalysis from conventional continuous gas-solid catalytic process. This paper summarized the knowledge and understanding of the NSR catalysis on supported Pt-BaO catalyst. The fundamental chemical processes over the NSR catalysts were discussed first, followed by the role of Pt, BaO and support material. Problems and prospects in the study of NSR catalysts were presented.

Key words: NO_x storage-reduction, lean NO_x abatement, Pt-BaO catalyst, low platinum catalyst, anti-sintering