Enhanced catalytic soot oxidation by Ce-based MOF-derived ceria nano-bar with promoted oxygen vacancy

Tsai, Y.-C., Lee, J., Kwon, E., Huang, C.-W., Huy, N. N., You, S. , Hsu, P.-S., Oh, W. D. and Lin, K.-Y. A. (2021) Enhanced catalytic soot oxidation by Ce-based MOF-derived ceria nano-bar with promoted oxygen vacancy. Catalysts, 11(9), 1128. (doi: 10.3390/catal11091128)

Abstract

As CeO2 is a useful catalyst for soot elimination, it is important to develop CeO2 with higher contact areas, and reactivities for efficient soot oxidation and catalytic soot oxidation are basically controlled by structures and surface properties of catalysts. Herein, a Ce-Metal organic framework (MOFs) consisting of Ce and benzene-1,3,5-tricarboxylic acid (H3BTC) is employed as the precursor as CeBTC exhibits a unique bar-like high-aspect-ratio morphology, which is then transformed into CeO2 with a nanoscale bar-like configuration. More importantly, this CeO2 nanobar (CeONB) possesses porou, and even hollow structures, as well as more oxygen vacancies, enabling CeONB to become a promising catalyst for soot oxidation. Thus, CeONB shows a much higher catalytic activity than commercial CeO2 nanoparticle (comCeO) for soot oxidation with a significantly lower ignition temperature (Tig). Moreover, while soot oxidation by comCeO leads to production of CO together with CO2, CeONB can completely convert soot to CO2. The tight contact mode also enables CeONB to exhibit a very low Tig of 310 °C, whereas the existence of NO also enhances the soot oxidation by CeONB to reduce the Tig. The mechanism of NO-assisted soot oxidation is also examined, and validated by DRIFTS to identify the formation and transformation of nitrogen-containing intermediates. CeONB is also recyclable over many consecutive cycles and maintained its high catalytic activity for soot oxidation. These results demonstrate that CeONB is a promising and easily prepared high-aspect-ratio Ce-based catalyst for soot oxidation.

• Item Type: Articles
• Keywords: MOFs, ceria, carbon black, catalytic oxidation, high aspect ratio.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: You, Dr Siming

Creator Roles

You, S.: Visualization

• Authors: Tsai, Y.-C., Lee, J., Kwon, E., Huang, C.-W., Huy, N. N., You, S., Hsu, P.-S., Oh, W. D., and Lin, K.-Y. A.
• College/School: College of Science and Engineering > School of Engineering > Systems Power and Energy
• Journal Name: Catalysts
• Publisher: MDPI
• ISSN: 2073-4344
• ISSN (Online): 2073-4344
• Published Online: 18 September 2021
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in Catalysis 11(9): 1128
• Publisher Policy: Reproduced under a Creative Commons License