Ultra-low temperature sintering and microwave dielectric properties of Mg-substituted SrCoV₂O₇ ceramics

SrCo1-xMgxV2O7 (x = 0–0.09) dielectrics were prepared via the solid state route and the effect of Mg substitution on the microwave dielectric properties of the ceramics was systematically investigated. In addition to the relative density and microstructure, the dielectric polarizability, packing fraction, lattice energy and bond valence also play a crucial role in controlling the dielectric properties of the ceramics at microwave frequencies. A high lattice energy representing a high structural stability leads to a low dielectric loss in the specimen. Fluctuated variation of the τf was highly related to the bond valence of the samples. Specimens with x = 0.07 at 660°C revealed the highest Q × f of 23,000 GHz along with an εr of 13.2 and a τf of – 95 ppm/°C and it is chemically compatible with the Al electrode, suggesting that the dielectric is highly promising for ULTCC applications.