| AVS 56th International Symposium & Exhibition | |
| Surface Science | Tuesday Sessions |
| Session SS3-TuA |
| Session: | Catalysis: Mechanisms & Morphology |
| Presenter: | Z.Q. Yu, Nanjing Normal University, China |
| Authors: | Z.Q. Yu, Nanjing Normal University, China P. Nachimuthu, Pacific Northwest National Laboratory M. Nandasiri, Pacific Northwest Natioanl Laboratory S.V.N.T. Kuchibhatla, Pacific Northwest Natioanl Laboratory Y.J. Kim, Hanbat National University, Korea M.H. Engelhard, Pacific Northwest National Laboratory V. Shutthanandan, Pacific Northwest National Laboratory W. Jiang, Pacific Northwest National Laboratory J. Szanyi, Pacific Northwest National Laboratory S. Thevuthasan, Pacific Northwest National Laboratory |
| Correspondent: | Click to Email |
Catalysts for NOx storage and reduction (NSR) are being developed to reduce the NOx emission from gasoline based internal combustion engines. BaO is considered to be potential NSR catalysts because of its strong interaction and an effective trapping of NO2. BaO is more reactive when BaO is present as non-stoichiometric BaO clusters rather than bulk BaO. In order to understand the reactivity, BaO was grown on YSZ(111) and CeO2(111)/YSZ(111) substrates by molecular beam epitaxy. In-situ reflection high-energy electron diffraction, ex-situ x-ray diffraction, atomic force microscopy and x-ray photoelectron spectroscopy have confirmed that the BaO grows as nanoclusters on YSZ(111) . During and following the growth under UHV conditions, BaO remains in single phase. The reaction of NO2 with the BaO nanoclusters in different sizes on YSZ(111) and CeO2(111)/YSZ(111) substrates was investigated using in situ high-resolution x-ray photoelectron spectroscopy (XPS). The adsorption of NO2 on the BaO nanoclusters at room temperature and the formation of Ba(NOx)2 species at room temperature and above were probed. In addition the in situ XPS data collected from the BaO nanocluesters prior to and following the reaction with NO2 were utilized to understand the morphology of BaO nanoclusters and the formation of Ba(NOx)2 species using Quases-Tougaard V5.1 software. These results are compared with the reported data from NO2 reaction with BaO film deposited onto an Al2O3/NiAl(110) substrate.