Topics in Catalysis

, 52:1746

Influence of Pt–Ba Proximity on NO x Storage–Reduction Mechanisms: A Space- and Time-Resolved In Situ Infrared Spectroscopic Study

Authors

  • Nobutaka Maeda
    • Department of Chemistry and Applied Biosciences, Institute for Chemical and BioengineeringETH Zurich
    • Department of Chemistry and Applied Biosciences, Institute for Chemical and BioengineeringETH Zurich
    • Department of Chemistry and Applied Biosciences, Institute for Chemical and BioengineeringETH Zurich
Original Paper

DOI: 10.1007/s11244-009-9342-x

Cite this article as:
Maeda, N., Urakawa, A. & Baiker, A. Top Catal (2009) 52: 1746. doi:10.1007/s11244-009-9342-x

Abstract

The influence of Pt–Ba proximity on the performance and mechanism of NO x storage–reduction (NSR) was investigated by a comparative study of Pt–Ba/CeO2, Pt/CeO2 and mechanically mixed Pt/CeO2–Ba/CeO2. NO x storage capacity, regeneration activity and selectivity to nitrogen and ammonia during periodic lean (NO + O2)–rich (H2) cycles were evaluated and the chemical gradients along the axial direction of the catalyst beds were monitored by space- and time-resolved in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). The presence of Ba and its proximity to Pt greatly influenced the NSR process. In particular, the proximity was crucial to achieve better utilization of bulk Ba components as well as enhancing selectivity to N2. The space-resolved approach is shown to be a powerful tool to understand the impact of the proximity of Pt and Ba constituents on the final NSR performance.

Keywords

NO x storage–reduction Pt–Ba proximity Mechanically mixed catalyst In situ spectroscopy Space- and time-resolution

Copyright information

© Springer Science+Business Media, LLC 2009