Fundamental Studies of Oxygen Storage Materials (Chuck Peden's BES Project - 26104)
EMSL Project ID
6694
Abstract
The goal of this research is to fill a gap in the fundamental understanding of catalyst activity and durability with respect to the transient NOx reduction performance of automotive catalytic converters. We are accomplishing this goal by obtaining detailed chemical kinetics data on idealized but well-characterized catalyst systems useful for understanding the important elementary converter reactions. A particular focus of the work is on how the catalytic chemistry is effected by the oxygen uptake, storage, and release processes carried out by the oxygen storage material. The fundamental understanding of critical rate-determining processes in this complex system will provide insight into the material properties required for improved, more durable catalysts. For example, we are elucidating and quantifying the mechanisms responsible for the improved performance with the use of ceria-zirconia mixtures relative to ceria alone formulations. For these latter studies, we have prepared and characterized a number of model, single crystal thin films of ceria with and without Zr-doping. More generally, a molecular-level description of the adsorption and reaction of various NOx species (NO, NO2, N2O) on specific oxide surface “active sites”, of relevance for a wide variety of catalytic NOx processes, is being obtained in this work.
Project Details
Project type
Exploratory Research
Start Date
2004-01-05
End Date
2006-11-13
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Epling WS, I Nova, and CHF Peden. 2008. "Preface." Catalysis Today 136(1-2):1-2. doi:10.1016/j.cattod.2008.03.008
Kittilstved KR, DA Schwartz, AC Tuan, SM Heald, SA Chambers, and DR Gamelin. 2006. "Direct kinetic correlation of carriers and ferromagnetism in Co2+ : ZnO." Physical Review Letters 97:037203-1 - 037203-4. doi:10.1103/PhysRevLett.97.037203
Kittilstved KR, DA Schwartz, AC Tuan, SM Heald, SA Chambers, and DR Gamelin. 2006. "Direct kinetic correlation of carriers and ferromagnetism in Co2+ : ZnO." Physical Review Letters 97:037203-1 - 037203-4. doi:10.1103/PhysRevLett.97.037203
Ozensoy E, CHF Peden, and J Szanyi. 2006. "Low Temperature H2O and NO2 Coadsorption on ?-Al2O3/NiAl(100) ultrathin films ." Journal of Physical Chemistry B 110(15):8025-8034.
Ozensoy E, DR Herling, and J Szanyi. 2008. "NOx Reduction on a Transition Metal-free γ-Al2O3 Catalyst Using Dimethylether (DME)." Catalysis Today 136(1-2):46-54
RG Tonkyn, SE Barlow, BE Koel, Zhao H, and CHF Peden. 2006. "Catalytic oxidation of HCN over a 0.5% Pt/Al2O3 catalyst." Applied Catalysis. B, Environmental 65(2006):282-290.
Szailer T, J Kwak, D Kim, J Szanyi, CM Wang, and CHF Peden. 2006. "Effects of Ba loading and calcination temperature on BaAl2O4 formation for BaO/Al2O3 NOx Storage and Reduction Catalysts." Catalysis Today 114(1):86-93.
White MA, ST Ochsenbein, and DR Gamelin. 2008. "Colloidal Nanocrystals of Wurtzite Zn 1-xCox0 (0 ? x ? 1) Models of Spinodal Decomposition in an Oxide Diluted Magnetic Semiconductor." Chemistry of Materials 20(22):7107-7116. doi:10.1021/cm802280g