Synthesis, phase stability and electrical characterisation of BINAVOX solid solutions
1997; Royal Society of Chemistry; Volume: 7; Issue: 10 Linguagem: Inglês
10.1039/a703629i
ISSN1364-5501
AutoresCraig J. Watson, Alison M. Coats, Derek C. Sinclair,
Tópico(s)Nonlinear Optical Materials Research
ResumoThe compositional range of ‘Bi4V2O11’ solid solutions containing Na has been determined by means of a phase diagram study using X-ray diffraction and electron probe microanalysis. The locus of the solid solution indicates that Na replaces V in the crystal structure and the BINAVOX family has the overall formula Bi4+yV2–y–xNaxO11–y–2x. The solid solution limits are temperature dependent and for samples prepared and air-cooled from 830 °C the limits are defined as 0.00<x<0.18 and 0.05<y 0.10 are thermodynamically unstable below ca. 720 °C but can be stabilised kinetically by rapid cooling from temperatures above ca. 750 °C. ac Impedance measurements demonstrate that BINAVOX materials are electrically inhomogeneous, exhibit temperature- and time-dependent conductivities and do not offer any significant advantages over the parent solid solution.
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