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Controlled Recrystallization of Hematite from Two Highly Different Phases of Ferric Trihydroxide

Published online by Cambridge University Press:  28 February 2011

Georges Denes
Affiliation:
Concordia University, Laboratory of Solid State Chemistry and Mössbauer Spectroscopy, Laboratories for Inorganic Materials, Department of Chemistry and Biochemistry, 1455 De Maisonneuve Blvd. W., Montreal, Quebec, H3G 1M8, Canada
P. Kabro
Affiliation:
Concordia University, Laboratory of Solid State Chemistry and Mössbauer Spectroscopy, Laboratories for Inorganic Materials, Department of Chemistry and Biochemistry, 1455 De Maisonneuve Blvd. W., Montreal, Quebec, H3G 1M8, Canada
M.C. Madamba
Affiliation:
Concordia University, Laboratory of Solid State Chemistry and Mössbauer Spectroscopy, Laboratories for Inorganic Materials, Department of Chemistry and Biochemistry, 1455 De Maisonneuve Blvd. W., Montreal, Quebec, H3G 1M8, Canada
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Abstract

Hematite Fe2O3, is a semiconductor, and its electrical properties are highly sensitive to the preparation methods and purity. Its precursors can be hydrated ferric oxides; however, these are usually obtained from poorly defined ferric gels, which are obtained by hydrolysis of an aqueous solution of a ferric salt by a base. We have designed a novel synthetic route to ferric hydroxide, by reaction of a peroxo-compound with an aqueous solution of a ferrous salt, which involves simultaneous oxidation of Fe(ll) to Fe(lll), and hydrolysis, in the same reaction process. The two kinds of ferric hydroxide are highly different, however, both give hematite by dehydration/recrystallization, however, the way this occurs for each is different.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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References

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