Microwave dielectric properties and chemical bond of novel spinel-structure Zn3Ga2SnO8 ceramics.

A novel low- ε r Zn 3 Ga 2 SnO 8 ceramic was prepared, and the phase composition and microstructural evolution were investigated. According to Rietveld refinement, TEM, and Raman spectroscopy, Zn 3 Ga 2 SnO 8 ceramics had a cubic spinel structure in which Zn1 occupied the tetrahedral sites, and Zn2/Ga1/Sn1 occupied the octahedral sites. The relative density and packing fraction significantly influence the ε r and Q × f of Zn 3 Ga 2 SnO 8 ceramics, respectively. Meanwhile, the P–V–L theory indicates that the contribution rate of Sn–O bonds to bond ionicity is 29.2 %, and that of Ga–O bonds to lattice energy is 37.5 %. The Zn 3 Ga 2 SnO 8 ceramics exhibit the best microwave dielectric properties (ε r = 10.6, Q × f = 88,725 GHz, and τ f = −25.1 ppm/°C) when sintered at 1320 °C. Given these advantages, Zn 3 Ga 2 SnO 8 ceramic has certain potential applications in millimeter-wave technology. [ABSTRACT FROM AUTHOR]