Fe-57 Mössbauer and Mo K-EXAFS Investigations of MoxFe3-xO4, an Interesting Mixed-Valent Oxide System

Bouet, L and Tailhades, Ph and Rousset, A and Kannan, KR and Verelst, M and Kulkarni, GU and Rao, CNR (1993) Fe-57 Mössbauer and Mo K-EXAFS Investigations of MoxFe3-xO4, an Interesting Mixed-Valent Oxide System. In: Journal of Solid State Chemistry, 102 (2). pp. 414-422.

PDF Mix.pdf - Published Version Restricted to Registered users only Download (290kB) | Request a copy

Abstract

Ferrites of the formula MoxFe3-xO4, prepared by a soft-chemistry route, show mixed valence states of both iron and molybdenum cations. Mössbauer studies show that Fe2+ and Fe3+ ions are present on both the A and B sites, giving Fe an average oxidation state between 2+ and 3+. Molybdenum is present in the 3+ and the 4+ states on the B sites. The presence of Mo in the 3+ state has been established by determining the Mo3+-O distance (2.2 Å), for the first time, by Mo K-EXAFS. The mixed valence of Fe on both the A and B sites and of Mo on the B sites is responsible for the fast electron transfer between the cations. All the Mössbauer parameters including the line width show a marked change at a composition (x ? 0.3) above which the concentration of Fe2+A increases rapidly.

Item Type:	Journal Article
Publication:	Journal of Solid State Chemistry
Publisher:	Elsevier Science
Additional Information:	Copyright of this article belongs to Elsevier Science.
Department/Centre:	Division of Chemical Sciences > Solid State & Structural Chemistry Unit
Date Deposited:	10 Feb 2011 09:39
Last Modified:	10 Feb 2011 09:39
URI:	http://eprints.iisc.ac.in/id/eprint/35471

Actions (login required)

View Item