This work was supported by the National 973-project of China (2009CB623302), NSFC projects of China (61025002, 109790365), and National Project of International Science and Technology Collaboration (2009DFA51820).
Microwave and Infrared Dielectric Response of Temperature Stable (1−x)BaMoO4–xTiO2 Composite Ceramics
Article first published online: 27 JUL 2011
© 2011 The American Ceramic Society
Journal of the American Ceramic Society
Volume 95, Issue 1, pages 232–237, January 2012
How to Cite
Guo, J., Zhou, D., Wang, H., Chen, Y., Zeng, Y., Xiang, F., Wu, Y., Yao, X. (2012), Microwave and Infrared Dielectric Response of Temperature Stable (1−x)BaMoO4–xTiO2 Composite Ceramics. Journal of the American Ceramic Society, 95: 232–237. doi: 10.1111/j.1551-2916.2011.04760.x
- Issue published online: 3 JAN 2012
- Article first published online: 27 JUL 2011
- Manuscript Accepted: 21 JUN 2011
- Manuscript Received: 20 APR 2011
- National 973-project of China. Grant Number: 2009CB623302
- NSFC projects of China. Grant Numbers: 61025002, 109790365
- National Project of International Science and Technology Collaboration. Grant Number: 2009DFA51820
The (1−x)BaMoO4–xTiO2 (x = 0.0, 0.2, 0.3, 0.338, 0.4, 0.5, 0.66) ceramics were synthesized by the conventional mixed-oxide process. The sintering behaviors, phase composition, chemical compatibility with silver, and microwave dielectric properties of pure (1−x)BaMoO4–xTiO2 ceramics and 0.662BaMoO4–0.338TiO2 ceramic with H3BO3–CuO addition were studied. Infrared reflectivity spectra of (1−x)BaMoO4–xTiO2 (0.2 ≤ x ≤ 0.4) composites were measured in the range of 50–4500 cm−1 at room temperature. X-ray diffraction analysis reveals that scheelite BaMoO4 and rutile TiO2 phase coexist with each other at 1275°C and both of them do not react with silver (Ag) at 850°C. When the mole fraction of TiO2 (x value) is 0.4, a temperature stable microwave dielectric material is obtained, with εr = 13.8, Q × f = 40 500 GHz (f = 8.02 G), and τf = −6.13 ppm/°C. Complex dielectric spectra gained from the infrared spectra were extrapolated down to microwave range, and they were in good agreement with the measured microwave permittivity and dielectric losses. With 5 wt% H3BO3 and 1 wt% CuO addition, the 0.662BaMoO4–0.338TiO2 ceramics can be sintered well below 900°C, and possess good microwave dielectric properties with εr = 14, Q × f = 48 360 GHz, and τf = +13.9 ppm/°C.