Microwave dielectric properties and chemical bond characteristics of low temperature firing Li3VO4 ceramic with low permittivity

Abstract

Low-fired Li3VO4 ceramics were fabricated and their sintering characteristics, intrinsic structure of the crystal, and microwave dielectric performances were discussed. After the Rietveld refinements, all samples showed the single orthorhombic Li3VO4 phase with the space group Pnm21 over the sintering temperature 700–820 °C for 2–6 h. The results presented that the permittivity, quality factor, and density exhibited a close correlation at different sintering conditions. The homogenous microstructures and outstanding dielectric performances were achieved upon sintering at 730 °C/4h: εr of 6.65, Q × f value of 15,700 GHz, and τf of −103 ppm/°C. The intrinsic characteristics of Li3VO4 compounds were also discussed by chemical bond theory. The results indicated that the V(1)–O bonds dominated the contribution to the dielectric properties of the Li3VO4 ceramics.