Temperature Stability of V2O5-Doped KNN-LS-BF Lead-Free Piezoelectric Ceramics

V₂O₅-doped Na_0.5K_0.5NbO₃-LiSbO₃-BiFeO₃ (KNN-LS-BF) lead-free piezoelectric ceramics were prepared by the traditional sintering method, and their temperature stability was studied. Characterization of the temperature dependences of dielectric and piezoelectric properties of the V₂O₅-doped KNN-LS-BF ceramics showed that V₂O₅ doping could significantly improve the temperature stability in the temperature range of 30°C to 420°C and cause a downward shift in the orthorhombic–tetragonal phase transition to below room temperature. It was also found that the V₂O₅-doped KNN-LS-BF ceramics possess good dielectric and piezoelectric properties (ε _r > 1066, tan δ < 4%, d ₃₃ > 185 pC/N, k _p > 0.25) in the temperature range of 30°C to 300°C.