Next Article in Journal / Special Issue
The Adsorption of Nitromethane on the Au (111) Surface
Previous Article in Journal / Special Issue
Reaction Mechanism and Control of Selectivity in Catalysis by Oxides: Some Challenges and Open Questions
Int. J. Mol. Sci. 2001, 2(5), 197-210; doi:10.3390/i2050197

Electronic Structure and Reactivity of TM-Doped La1-xSrxCoO3 (TM=Ni, Fe) Heterogeneous Catalysts

1, 1,* , 1, 1, 1, 1, 1, 1 and 2
1 Department of Physics, UMIST, PO Box 88, Manchester M60 1QD, UK 2 Synetix, PO Box 1, Belasis Avenue, Billingham, Cleveland, TS23 1LB, UK
* Author to whom correspondence should be addressed.
Received: 26 September 2001 / Accepted: 6 November 2001 / Published: 13 November 2001
Download PDF [198 KB, uploaded 19 June 2014]


The catalytic properties of LaCoO3 in aqueous oxidation are explored as a function of doping. Both Sr substitution for La and Fe/Ni substitution for Co are studied. The reaction of interest is the aqueous epoxidation of crotyl alcohol with hydrogen peroxide. The reaction products are measured using GC, and the decomposition of hydrogen peroxide is studied using the volume of oxygen evolved during reaction. Strong variations in the activity to epoxide formation are observed, with Fe-doped samples being rather inactive in the reaction. SR VUV photoemission is used to explore the surface reactivity of the ceramic catalysts in aqueous solution, using H2O as a probe molecule. These measurements are complemented by XANES measurements designed to probe the local defect structure and XPS measurements of surface composition. We relate the observed catalytic activity to the defect structure of the doped materials. In Ni-doped materials, oxygen vacancies appear to be the predominant defect, whereas in Fe-doped samples, electron holes are stabilized on Fe, leading to very different catalytic behaviour. Surface studies in combination with AA measurements reveal some dissolution of the catalyst into solution during the reaction. The surface reactivity to water is influenced by the TM d electron count, with water binding more strongly to Fe-doped materials than to those containing Ni. The influence of these factors on the rate of the unwanted hydrogen peroxide decomposition reaction and hence on activity in epoxidation is discussed.
Keywords: Aqueous epoxidation; perovskite; La1-xSrxCoO3; XANES; XPS Aqueous epoxidation; perovskite; La1-xSrxCoO3; XANES; XPS
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Share & Cite This Article

Further Mendeley | CiteULike
Export to BibTeX |
MDPI and ACS Style

Grice, S.C.; Flavell, W.R.; Thomas, A.G.; Warren, S.; Marr, P.G.D.; Jewitt, D.E.; Khan, N.; Dunwoody, P.M.; Jones, S.A. Electronic Structure and Reactivity of TM-Doped La1-xSrxCoO3 (TM=Ni, Fe) Heterogeneous Catalysts. Int. J. Mol. Sci. 2001, 2, 197-210.

View more citation formats

Related Articles

Article Metrics

For more information on the journal, click here


Cited By

[Return to top]
Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert