title: Structural and magnetic properties of Zn-substituted cobalt ferrites prepared by co-precipitation method.
abstract: Zn substituted cobalt ferrite spinels with the general formula Zn(x)Co(1-x)Fe(2)O(4) (with x varying from 0 to 0.5) were synthesized by a co-precipitation method and calcined at 500 °C and 800 °C. It was found that Zn substitution has a big effect in decreasing the Curie temperature (T(c)), from around 440 °C for the undoped sample to ~180 °C with x = 0.5. However, these values were also strongly affected by the pre-calcination temperature of the samples, thus T(C) shifts from ~275 °C for the x = 0.3 sample to ~296 °C after calcination at 500 °C and 800 °C respectively. These effects are due to facilitation of demagnetisation by substitution of the non-magnetic Zn ions and by production of very small nanoparticles. The latter are removed by higher temperature calcinations and so T(C) increases.
authors.affiliation: Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Cardiff CF10 3AT, UK.
authors.forename: Polina
authors.initials: P
authors.lastname: Yaseneva
authors.forename: Michael
authors.initials: M
authors.lastname: Bowker
authors.forename: Graham
authors.initials: G
authors.lastname: Hutchings
mesh_terms: D003035:Cobalt / Q000737:chemistry*; D005290:Ferric Compounds / Q000737:chemistry*; D008280:Magnetics; D044366:Transition Temperature; D015032:Zinc / Q000737:chemistry*
chemical_list: D005290:Ferric Compounds; C001215:ferrite; D003035:Cobalt; D015032:Zinc