Jump to main content
Jump to site search

Issue 22, 2017
Previous Article Next Article

Catalytically active ceria-supported cobalt–manganese oxide nanocatalysts for oxidation of carbon monoxide

Author affiliations

Abstract

A low-concentration cobalt (∼6 at%) and manganese (∼3 at%) bimetallic oxide catalyst supported on ceria nanorods (CoMnOx/CeO2), as well as its related single metal oxide counterparts (CoOx/CeO2 and MnOx/CeO2) was synthesized via a deposition–precipitation approach. The fresh samples after air-calcination at 400 °C were tested under the reaction conditions of CO oxidation, and showed the following order of reactivity: CoMnOx/CeO2 > CoOx/CeO2 > MnOx/CeO2. X-ray diffraction (XRD) and transmission electron microscopy (TEM) data identified that the structure of the CeO2 support was maintained during deposition of metal (Co, Mn) ions while the corresponding vis-Raman spectra verified that more oxygen vacancies were created after deposition–precipitation than those in pure ceria nanorods. Aberration-corrected, high-angle, annular dark-field scanning transmission electron microscopy (HAADF-STEM) images with the help of electron energy loss spectroscopy (EELS) analyses determined two types of cobalt species, i.e. ultra-fine clusters (<2 nm) and smaller nanocrystals (up to 5 nm) in CoOx/CeO2 while only bigger nanostructures (∼10 nm) of cobalt–manganese oxides in CoMnOx/CeO2. X-ray absorption fine structure (XAFS) measurements demonstrated the presence of a cubic Co3O4 phase in all the cobalt-based catalysts. The fitting results of the extended X-ray absorption fine structure (EXAFS) indicated that the introduction of the secondary metal (Mn) oxide significantly enhanced the two-dimensional growth of cobalt oxide nanostructures on the surface of CeO2. Therefore, the enhanced activity of CO oxidation reaction over the bimetallic cobalt–manganese oxide nanocatalyst can be attributed to the higher crystallinity of the Co3O4 phase in this work.

Graphical abstract: Catalytically active ceria-supported cobalt–manganese oxide nanocatalysts for oxidation of carbon monoxide

Back to tab navigation

Supplementary files

Publication details

The article was received on 29 Mar 2017, accepted on 29 Apr 2017 and first published on 05 May 2017


Article type: Paper
DOI: 10.1039/C7CP02004J
Citation: Phys. Chem. Chem. Phys., 2017,19, 14533-14542
  •   Request permissions

    Catalytically active ceria-supported cobalt–manganese oxide nanocatalysts for oxidation of carbon monoxide

    X. Wang, L. Du, M. Du, C. Ma, J. Zeng, C. Jia and R. Si, Phys. Chem. Chem. Phys., 2017, 19, 14533
    DOI: 10.1039/C7CP02004J

Search articles by author

Spotlight

Advertisements