Gibbs energy of formation of CuCrO4 and phase relations in the system Cu-Cr-O below 735 K

Jacob, KT and Kale, GM and Waseda, Y (1992) Gibbs energy of formation of CuCrO4 and phase relations in the system Cu-Cr-O below 735 K. In: Thermochimica Acta, 208 (28). pp. 341-348.

PDF 195._Cu-Cr-O._TA._1992.pdf - Published Version Restricted to Registered users only Download (494kB) | Request a copy

Abstract

A solid state galvanic cell incorporating yttria-stabilized zirconia electrolyte and ruthenium(IV) oxide electrodes has been used to measure the equilibrium chemical potential of oxygen corresponding to the decomposition of CuCrO4 in the range 590–760 K. For the reaction CuO(tenorite) + CuCr2O4(spinel) + 1.5O2(g)→2CuCrO4(orth), ΔGXXX = −183540 + 249.6T(±900) J mol−1. The decomposition temperature of CuCrO4 in pure oxygen at a pressure of 1.01 × 105 Pa is 735(±1) K. By combining the results obtained in this study with data on the Gibbs energy of formation of CuCr2O4 and CuCrO2 reported earlier, the standard Gibbs energy of formation of CuCrO4 and the phase relations in the system Cu-Cr-O at temperatures below 735 K have been deduced. Electron microscopic studies have indicated that the decomposition of CuCrO4 to CuCr2O4 is topotactic.

Item Type:	Journal Article
Publication:	Thermochimica Acta
Publisher:	Elsevier Science
Additional Information:	Copyright of this article belongs to Elsevier Science.
Department/Centre:	Division of Mechanical Sciences > Materials Engineering (formerly Metallurgy)
Date Deposited:	09 Dec 2011 09:02
Last Modified:	09 Dec 2011 09:02
URI:	http://eprints.iisc.ac.in/id/eprint/42680

Actions (login required)

View Item