Phase Formation Mechanism and Piezoelectric Behaviour of NaNbO₃ Ceramic

The solid state reaction route is adopted to synthesize NaNbO3 with the aim to examine their structural, morphological and electrical behaviour of material with sintering time. The crystal phase is formed without any secondary phase at calcination temperature 800 degrees C. The article shows the scope of material to be used as a sensor in piezoelectric applications. The synthesized material has been avoided to heat for longer time and has been sintered at 2 h, 4 h and 6 h. The refinement of experimental X-ray diffraction pattern displays crystallization of material in Orthorhombic phase with space group Pbcm and lattice parameters a = 5.513752 angstrom, b = 5.568852 angstrom, c = 15.52854 angstrom, alpha = beta = gamma = 90 degrees. A gaussian distribution of grain size with statistical average 0.722 mu m, 0.841 mu m and 0.842 mu m has been observed for NN02, NN04 and NN06 respectively. The NN04 shows maximum piezoelectric coefficient d(33)* = 110 pm V-1, piezoelectric strain 0.0021% and smallest as asymmetric factor Y-s = 0.204 with respect to other investigated samples.