TY - JOUR
T1 - Cooling rate effects on the electrical properties of TiO2-based varistor
AU - Hsiang, Hsing I.
AU - Wang, Shi Shu
N1 - Funding Information:
The authors would like to express their thanks to the National Science Council of the Republic of China for financial support of this project (NSC92-2216-E-006-21).
PY - 2006/3/15
Y1 - 2006/3/15
N2 - The cooling rate effects on the microstructure development and electrical properties of TiO2 ceramics are studied using transmission electron microscopy (TEM), energy dispersion spectrometer (EDS) and X-ray diffractometer (XRD). Barium and bismuth were exsolved during cooling and reacted with rutile to form secondary phases, Ba2Ti9O20 and Bi 2Ti4O11. Therefore, the acceptor concentration of Bi+3 (BiTi′) in the rutile grain near the grain boundary areas in furnace-cooled samples were lower than that in quenched samples. As the acceptor concentration decreased, the depletion width and barrier height decreased. Consequently, the quenched samples possessed higher nonlinear exponent (α) values than furnace-cooled samples.
AB - The cooling rate effects on the microstructure development and electrical properties of TiO2 ceramics are studied using transmission electron microscopy (TEM), energy dispersion spectrometer (EDS) and X-ray diffractometer (XRD). Barium and bismuth were exsolved during cooling and reacted with rutile to form secondary phases, Ba2Ti9O20 and Bi 2Ti4O11. Therefore, the acceptor concentration of Bi+3 (BiTi′) in the rutile grain near the grain boundary areas in furnace-cooled samples were lower than that in quenched samples. As the acceptor concentration decreased, the depletion width and barrier height decreased. Consequently, the quenched samples possessed higher nonlinear exponent (α) values than furnace-cooled samples.
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U2 - 10.1016/j.mseb.2005.11.001
DO - 10.1016/j.mseb.2005.11.001
M3 - Article
AN - SCOPUS:33344464958
VL - 128
SP - 25
EP - 29
JO - Materials Science and Engineering B: Solid-State Materials for Advanced Technology
JF - Materials Science and Engineering B: Solid-State Materials for Advanced Technology
SN - 0921-5107
IS - 1-3
ER -