| Abstract |
In this work, we investigate the giant dielectric properties of (Ga0.5Nb0.5)xTi1-xO2(where x=0.01,
0.025, 0.05 and 0.1) prepared by a solid state reaction method.The phase composition,microstructure,and
oxidation statesare characterized by X-ray diffraction, field-emission scanning electron microscopy
and X-ray photoelectron spectroscopy, respectively.The single phase of rutile-TiO2with dense microstructure
are obtained in all sintered (Ga0.5Nb0.5)xTi1-xO2ceramics. The existence of Ti3+
and oxygen vacancies are confirmed. The dielectric constant increased with increasing co-doping
(Ga+Nb)concentration. Excellent dielectric properties are obtained in the (Ga0.5Nb0.5)xTi1-xO2ceramic
with x= 0.1 sintered at 1550oC for 1h.Low dielectric loss tangent (< 0.05) and very large dielectric
constant (e = 41267) with excellent temperature coefficient (<15%) in the range of -70 to 170 oC are
achieved. The giant dielectric response over a broad temperature range of the (Ga0.5Nb0.5)xTi1-
xO2ceramics is primarily attributed to the interfacial polarization at internal insulating interfaces. |
Publication
Journal Publication
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