Jacob, KT and Pandit, SS (1985) Gibbs Energy of Formation of Cobalt Divanadium Tetroxide. In: Journal of Solid State Chemistry, 60 (2). pp. 237-243.
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Abstract
The Gibbs energy of formation of V2O3-saturated spinel CoV2O4 has been measured in the temperature range 900–1700 K using a solid state galvanic cell, which can be represented as Pt, Co + CoV2O4 + V2O3/(CaO) ZrO2/Co + CoO, Pt. The standard free energy of formation of cobalt vanadite from component oxides can be represented as CoO (rs) + V2O3 (cor) → CoV2O4 (sp), ΔG° = −30,125 − 5.06T (± 150) J mole−1. Cation mixing on crystallographically nonequivalent sites of the spinel is responsible for the decrease in free energy with increasing temperature. A correlation between “second law” entropies of formation of cubic 2–3 spinels from component oxides with rock salt and corundum structures and cation distribution is presented. Based on the information obtained in this study and trends in the stability of aluminate and chromite spinels, it can be deduced that copper vanadite is unstable.
Item Type: | Journal Article |
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Publication: | Journal of Solid State Chemistry |
Publisher: | Elsevier Science |
Additional Information: | The copyright of this article belongs to Elsevier Science |
Department/Centre: | Division of Mechanical Sciences > Materials Engineering (formerly Metallurgy) |
Date Deposited: | 23 Jul 2009 04:47 |
Last Modified: | 19 Sep 2010 05:31 |
URI: | http://eprints.iisc.ac.in/id/eprint/20158 |
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