Structural, ferroelectric and piezoelectric properties of lithium doped sodium potassium niobate.

Currently, K0.5Na0.5NbO3 (KNN) based ceramics are the most promising family of lead-free piezoelectric. The composition [(K0.5−x/2 Na0.5−x/2Lix) NbO3 (x=0.01, 0.05, 0.07): LKNN] have been fabricated by standard solid-state reaction method. X-ray diffraction analysis of samples show composition dependent structural changes. The structure is found to be orthorhombic for x=0.01 and x=0.05. A morphotropic phase boundary between orthorhombic and tetragonal phases is found for x=0.07. LKNN ceramics with x=0.01 exhibits enhanced electro strains properties with dynamic d33* value of 418 pm/V, and a remnant polarization (Pr) of 12.6 µC/cm2. [ABSTRACT FROM AUTHOR]