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Magnetic characterization of calcium-nickel-potassium oxide catalysts

Published online by Cambridge University Press:  03 March 2011

Dale L. Perry
Affiliation:
Lawrence Berkeley Laboratory, Berkeley, California 94720
Paul Berdahl
Affiliation:
Lawrence Berkeley Laboratory, Berkeley, California 94720
Charles Perrino
Affiliation:
Lawrence Berkeley Laboratory, Berkeley, California 94720
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Abstract

SQUID magnetometer characterization of Ca–Ni–K–O catalyst materials reveals complex magnetic behavior. The magnetic properties are generally determined by the antiferromagnetic material NiO, but samples with traces of elemental nickel show marked effects of ferromagnetism. Potassium doping enhances the formation of metallic nickel. Further deviations from bulk NiO properties can be attributed to NiO particle size effects (superparamagnetism) and to the presence of paramagnetic impurities, possibly Ni3+ ions.

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Articles
Copyright
Copyright © Materials Research Society 1994

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