Microwave dielectric properties of low-temperature sinterable α-MoO3. Issue 4 (April 2018)

• Record Type: Journal Article
• Authors: Varghese, Jobin; Siponkoski, Tuomo; Nelo, Mikko; Sebastian, Mailadil Thomas; Jantunen, Heli
• Is Part Of: Journal of the European Ceramic Society. Volume 38:Issue 4(2018)
• Page Start: 1541
• Page End: 1547
• Publication Date: 2018-04
• Subjects: Microwave ceramics -- Sintering -- Raman spectroscopy -- X-ray photoelectron spectroscopy and scanning electron microscopy; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2017.11.027
• Languages: English
• ISSNs: 0955-2219

Abstract

Graphical abstract: Raman spectrum, low temperature sintering and high quality factor α-MoO3 binary ceramics. Abstract: The α-MoO3 ceramics were prepared by uniaxial pressing and sintering of MoO3 powder at 650 °C and their structure, microstructure, densification and sintering and microwave dielectric properties were investigated. The sintering temperature of α-MoO3 was optimized based on the best densification and microwave dielectric properties. After sintering at 650 °C the relative permittivity was found to be 6.6 and the quality factor was 41, 000 GHz at 11.3 GHz. The full-width half-maximum of the A1g Raman mode of bulk α-MoO3 at different sintering temperatures correlated well with the Qf values. Moreover, the sintered samples showed a temperature coefficient of the resonant frequency of −25 ppm/°C in the temperature range from −40 to 85 °C and they exhibited a very low coefficient of thermal expansion of ±4 ppm/°C. These microwave dielectric properties of α-MoO3 will be of great benefit in future MoO3 based materials and their applications.