Influence of V substitutions on sintering behaviors and microwave dielectric properties of Ba4LiNb3O12 ceramic

In this study, a series of Ba4Li(Nb1-xVx)(3)O-12 (x = 0.05 similar to 0.3) ceramics were synthesized using the solid-state reaction method. X-ray powder diffraction (XRD) analysis shows that the composite ceramics contain both Ba4LiNb3O12 and Ba-3(VO4)(2) phases, without any other phases present. The grains consist of Ba4LiNb3O12 and Ba-3(VO4)(2), as illustrated by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). Additionally, with the increase of V content, the grain size decreases, and the epsilon r (microwave dielectric constant) decreases, the tau(f) (resonant frequency temperature coefficient) value decreases, and the Qxf value increases (where Q = quality factor = 1 / dielectric loss, and f = resonant frequency). The densest Ba4Li(Nb0.7V0.3)(3)O-12, with a epsilon r of 31.3, tau(f) of + 70 ppm/degrees C, and high Qxf of 42 850 GHz, was obtained at a sintering temperature of 1350 degrees C. Furthermore, the addition of 5 wt.% BaCu(B2O5) (BCB) into Ba4Li(Nb0.7V0.3)(3)O-12 resulted in obtaining dense ceramics at a sintering temperature of 925 degrees C, with a epsilon r of 23.5, a high Qxf value of 14 370 GHz, and tau(f) of + 88 ppm/degrees C. Further investigations have shown that Ba4Li(Nb1-xVx)(3)O-12 ceramics are chemically compatible with Ag, suggesting its potential use in low-temperature cofired ceramics technology.