Dielectric, Piezoelectric, Pyroelectric Properties and Polymorphic Phase Transition of 0.95 (KxNa1-x) NbO3-0.05LiSbO3 Lead-free Ferroelectric Ceramics

0.95 (KxNa1-x) NbO3-0.05 LiSbO3 (KNN-LS-X) (X=0.4-0.5) lead-free ceramics were prepared by conventional solid method. The effect of K/Na ratio on the dielectric, piezoelectric, pyroelectric and polymorphic phase transition was studied. The results show that the electrical properties strongly depend on the K/Na ratio. The KNN-LS-X(X=0.45) ceramics exhibit enhanced properties (epsilon(r)=891.267, d(33)=222pC/N, K-p =0.43517, Q(m)=64.72, p=15x10(-4)C/m(2)K). Enhanced electrical properties of the KNN-LS-X (X=0.45) ceramics could be attributed to the effect of K/Na ratio modifying the polymorphic orthorhombic-tetragonal phase transition temperature to room temperature, which could make KNN-LS-X (X=0.45) ceramics use as a new ferroelectric sensor.