Artículos de revistas
Experimental study of the structural, microscopy and magnetic properties of Ni-doped SnO(2) nanoparticles
Fecha
2010Registro en:
JOURNAL OF NON-CRYSTALLINE SOLIDS, v.356, n.52-54, Special Issue, p.2960-2964, 2010
0022-3093
10.1016/j.jnoncrysol.2010.06.081
Autor
ARAGON, F. H.
COAQUIRA, J. A. H.
HIDALGO, P.
BRITO, S. L. M.
GOUVEA, D.
CASTRO, R. H. R.
Institución
Resumen
A polymer precursor method has been used to synthesize Ni-doped SnO(2) nanoparticles. X-ray diffraction (XRD) data analyses indicate the exclusive formation of nanosized particles with rutile-type phase (tetragonal SnO(2)) for Ni contents below 10 mol%. In this concentration range, the particle sizes decrease with increasing Ni content and a bulk solid solution limit was determined at similar to 1 mol%. Ni surface enrichment is present at concentrations higher than the solution limit. Only above 10 mol% Ni. the formation of a second NiO-related phase has been determined. Magnetization measurements suggest the occurrence of ferromagnetism for samples in the solid solution regime (below similar to 1 mol%). This ferromagnetism is associated with the exchange interaction between electron spins trapped on oxygen vacancies, and is enhanced as the amount of Ni(2+) substituting at Sn(4+) sites increases. Above the solid solution limit, ferromagnetism is destroyed by the Ni surface enrichment and the system behaves as a paramagnet. (C) 2010 Elsevier B.V. All rights reserved.