%0 Journal Article
%T Electrical characterization by impedance spectroscopy of Zn7Sb2O12 ceramic
%A Nobre
%A Marcos A. de Lima
%A Lanfredi
%A Silvania
%J Materials Research
%D 2003
%I ABM, ABC, ABPol, SBCC, SBCr, SBMM, SBPMat
%R 10.1590/S1516-14392003000200007
%X impedance spectroscopy technique was used to investigate the electric properties of zn7sb2o12, an electroceramic with inverse spinel type structure. the electric characterization of the zn7sb2o12 semiconducting ceramic was performed at temperature from 250 to 550 ˇăc, in the frequency range from 5 hz to 13 mhz. zinc antimoniate phase was synthesized by the polymeric precursors method. the bulk resistance curve as a function of temperature exhibits a thermistor behavior with negative temperature coefficient. the bulk conductivity follows the arrhenius law with two linear branches of different slopes positioned at around a region of transition, 450 ˇăc > t > 350 ˇăc. the activation energy values at low temperature (< 350 ˇăc) and high temperature (> 450 ˇăc) are equals to 0.78 and 0.61 ev, respectively. the existence of a phase transition limiting these regions is discussed.
%K varistor
%K spinel
%K semiconductor
%K impedance spectroscopy.
%U http://www.scielo.br/scielo.php?script=sci_abstract&pid=S1516-14392003000200007&lng=en&nrm=iso&tlng=en