Strobel R., Piacentini M., Maciejewski M., Baiker A., Pratsinis S.E.
ETH Zürich, CH
Keywords: catalysis, flame synthesis, nanoparticles, NOx storage reduction
NOx storage reduction (NSR) catalysts are applied for the abatement of NOx from engines operating under lean conditions, where conventional TWC catalysts are inefficient. Here, a novel two-nozzle flame spray pyrolysis (FSP) process was developed for one-step synthesis of Pt/Ba/Al2O3 NSR catalysts, which conventionally are prepared by wet-phase processes. The use of two nozzles separating the formation of Al and Ba resulted in the formation of individual BaCO3 and Al2O3 nanoparticles well-mixed at the nano level. In contrast, amorphous Ba species dispersed over the Al2O3 particles were formed by the conventional single nozzle FSP process. NO pulse experiments revealed no NOx storage capacity for Pt/Ba/Al2O3 made with one nozzle, but good storage on the catalysts made with two nozzles. In contrast to impregnated Pt/Ba/Al2O3, higher Ba loadings even increased the relative amount of Ba involved in the NOx storage process. This can be attributed to the absence of HT-BaCO3 in flame-made catalysts
Journal: TechConnect Briefs
Volume: 4, Technical Proceedings of the 2007 NSTI Nanotechnology Conference and Trade Show, Volume 4
Published: May 20, 2007
Pages: 183 - 186
Industry sector: Advanced Materials & Manufacturing
Topic: Nanoparticle Synthesis & Applications
ISBN: 1-4200-6376-6