Enhancing piezoelectric properties by introducing Ni ion into B-site of Li/Sb-modified (K,Na)NbO3 Pb-free piezoceramics

By introducing Ni ion into the B-site of perovskite lattice, (K0.47Na0.51Li0.02)(Nb0.94-xSb0.06Nix)O-3 (KNN-LSN, x = 0, 0.002, 0.005, and 0.008) Pb-free piezoceramics were prepared by solid state reaction method. The effect of Ni doping amounts on the structure and electrical properties of KNN-LSN ceramics were investigated. XRD results showed that all ceramics had pure orthorhombic perovskite structure. The introduction of Ni ion into B-site of KNN-LSN ceramics effectively improved the electrical properties. The optimal electrical properties of d(33) = 192 pC/N, k(p) = 38.6%, Q(m) = 128, epsilon(r) = 756, tan delta = 0.025, P-r = 25.6 mu C/cm(2), and E-c = 1.21 kV/mm were obtained when Ni doping amount x = 0.005, indicating that this ceramic was a promising Pb-free candidate for practical use. (C) 2012 The Ceramic Society of Japan. All rights reserved.