Effects of Nb2O5 Doping on the Microwave Dielectric Properties and Microstructures of Bi2Mo2O9 Ceramics. Issue 5 (28th February 2013)

• Record Type: Journal Article
• Authors: Lee, Ying‐Chieh; Chiu, Jam‐Da; Chen, Yu Hong; Randall, C. A.
• Is Part Of: Journal of the American Ceramic Society. Volume 96:Issue 5(2013)
• Page Start: 1477
• Page End: 1482
• Publication Date: 2013-02-28
• Subjects: Ceramics -- Periodicals; 620.1405
• DOI: 10.1111/jace.12204
• Languages: English
• ISSNs: 0002-7820

Abstract

<abstract abstract-type="main" xml:lang="en" id="jace12204-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>This study investigated the effects of the addition of Nb<sub>2</sub>O<sub>5</sub> and sintering temperature on the properties of Bi<sub>2</sub>Mo<sub>2</sub>O<sub>9</sub> ceramics. The ceramics were sintered in air at temperatures ranging from 620°C to 680°C. The addition of small amounts of Nb<sub>2</sub>O<sub>5</sub> as a dopant significantly affected the crystalline phase and the microwave dielectric properties of the Bi<sub>2</sub>Mo<sub>2</sub>O<sub>9</sub> ceramics. The secondary phase, γ‐Bi<sub>2</sub>MoO<sub>6</sub>, was observed when Nb<sub>2</sub>O<sub>5</sub> was added. However, unlike the Bi<sub>2</sub>Mo<sub>2</sub>O<sub>9</sub> ceramic without Nb<sub>2</sub>O<sub>5</sub> sintered above 645°C, the ceramics with 3 mol% Nb<sub>2</sub>O<sub>5</sub> contained no γ‐Bi<sub>2</sub>MoO<sub>6</sub> when sintered at 660°C. The <italic>Q </italic>×<italic> f</italic> value and τ<sub><italic>f</italic></sub> of the Bi<sub>2</sub>Mo<sub>2</sub>O<sub>9</sub> ceramics were improved by Nb<sub>2</sub>O<sub>5</sub> doping. The Bi<sub>2</sub>Mo<sub>2</sub>O<sub>9</sub> ceramics doped with 2 mol% Nb<sub>2</sub>O<sub>5</sub> exhibited the best microwave dielectric properties, with a permittivity of 36.5, a <italic>Q </italic>×<italic> f</italic> value (<italic>f</italic> = resonant frequency, <italic>Q </italic>= 1/dielectric loss at <italic>f</italic>) of 14100 GHz and τ<sub><italic>f</italic></sub> of +5.5 ppm/°C after sintering at 620°C.</p> </abstract>