Crystal structures and microwave dielectric properties of novel low-permittivity Ba1-xSrxZnSi3O8 ceramics. (April 2019)

• Record Type: Journal Article
• Authors: Song, Xiao-Qiang; Du, Kang; Li, Jie; Muhammad, Raz; Lu, Wen-Zhong; Wang, Xiao-Chuan; Lei, Wen
• Is Part Of: Materials research bulletin. Volume 112(2019)
• Page Start: 178
• Page End: 181
• Publication Date: 2019-04
• Subjects: Microwave dielectric properties -- Zinc-feldspar -- Low-relative permittivity; Materials -- Periodicals; Crystal growth -- Periodicals; Matériaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Crystal growth; Materials; Periodicals; 620.11
• DOI: 10.1016/j.materresbull.2018.12.026
• Languages: English
• ISSNs: 0025-5408

Abstract

Graphical abstract: Highlights: Ba1- x Sr x ZnSi3 O8 ( x = 0.2-0.8) solid solutions with monoclinic structure (P21/m) were obtained using the solid-state method. SrZnSi3 O8 single phase with triclinic structure (P-1) was achieved and its lattice structure was identified for the first time. The most excellent microwave dielectric properties ( ε r = 6.12, Q × f = 78064 GHz, and τf = −33.2 ppm/°C) were obtained for SrZnSi3 O8 . Abstract: Ba1- x Sr x ZnSi3 O8 ( x = 0.2–1.0) microwave dielectric ceramics were synthesized using the solid-state method at the temperature from 1087 °C to 1150 °C for 3 h. All compositions showed a single phase for Ba1- x Sr x ZnSi3 O8 when x increased from 0.2 to 1.0, and a phase transition from monoclinic to triclinic structure occurred between 0.8 and 1.0. The relative permittivity of Ba1- x Sr x ZnSi3 O8 ceramics decreased from 6.57 to 6.12 when the Ba 2+ ions substituted by Sr 2+ ions. However, the quality factor initially decreased from 34, 735 GHz ( x = 0.2) to 28, 986 GHz ( x = 0.4) and subsequently increased monotonously. The variation in the temperature coefficient of resonant frequency showed an opposite, slightly changing trend compared with that of the quality factor. A novel single-phase SrZnSi3 O8, which possesses good microwave dielectric properties of ε r = 6.12, Q × f = 78, 064 GHz, and τf = −33.2 ppm/°C, was obtained for the first time at the sintering temperature of 1150 °C.