Effect of PbO excess on the formation of lead magnesium niobate perovskite by the columbite method
Contribuinte(s) |
Universidade Estadual Paulista (UNESP) |
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Data(s) |
20/05/2014
20/05/2014
15/03/2004
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Resumo |
The effect of lead excess on the pyrochlore-type formation in Pb(Mg1/3Nb2/3)O-3 (PMN) powders has been investigated. The polymeric precursor method was used in the synthesis of the columbite in association to the partial oxalate method to synthesize the PMN powder samples. Structure refinement of the columbite precursor and PMN powders was carried out using the Rietveld method. The quantitative phase analysis showed that the amount of perovskite phase is not affected by PbO excess, but a great excess drives the pyrochlore-type formation so that 3 wt.% of PbO causes the predominance of Mg-containing pyrochlore phase. Using the refined data obtained from the Rietveld refinement, the compositional fluctuation in the perovskite phase was calculated from Nb/Mg ratio values and Pb occupation factor. Mg inclusion occurs concomitant with Ph one into PMN perovskite phase and this effect is directed by PbO excess during powder synthesis. (C) 2003 Elsevier B.V. All rights reserved. |
Formato |
107-111 |
Identificador |
http://dx.doi.org/10.1016/j.matchemphys.2003.11.013 Materials Chemistry and Physics. Lausanne: Elsevier B.V. Sa, v. 84, n. 1, p. 107-111, 2004. 0254-0584 http://hdl.handle.net/11449/37150 10.1016/j.matchemphys.2003.11.013 WOS:000188857400017 |
Idioma(s) |
eng |
Publicador |
Elsevier B.V. |
Relação |
Materials Chemistry and Physics |
Direitos |
closedAccess |
Palavras-Chave | #ceramics #Pb(Mg1/3Nb2/3)O-3 #chemical synthesis #phase transitions #Rietveld method |
Tipo |
info:eu-repo/semantics/article |