Dielectric properties of Na1−xKxNbO3, near x = 0.5 morphotropic phase region

Sodium-potassium niobate (Na1−xKxNbO3) ceramic pellets, with x = 0.490, 0.495, 0.500, 0.505 and 0.510, were prepared by solid state reaction method with double sintering. With varying potassium content (x), dielectric properties and X-ray diffraction (XRD) peaks shifting pattern exhibit strong compositional dependence. Among the prepared compositions, a break in the XRD peaks shifting tendency, and minimum dielectric constant, loss tangent and Electric conductivity indicate a morphotropic phase transition type behavior, at the composition with x = 0.500.