Analyse of structural and electrical properties of NaBa(2-x)Nd2x/3Nb5O15 solid solution with (0 ≤ x ≤1)

The structural and electrical properties of NaBa(2-x)Nd2x/3Nb5O15 ceramics were reported. All samples were prepared by the conventional solid-state reaction. A Room temperature X-ray study has allowed identifying the stabilization of tetragonal Tungsten Bronzes (TTB) structure with P4bm as space group for low Nd3+ concentration, whereas a centrosymmetric space group P4/mbm has been revealed for the high concentration. The dielectric study carried out on the prepared ceramics showed that the studied system undergo a behavior change from normal ferroelectric to a relaxor one with the increasing Neodymium amount. The complex impedance spectroscopy highlighted a thermally activated relaxation process in our samples. A short-range relaxation is proposed for x = 0.3 sample, while a possible coexistence of both localized and long-range relaxation for x = 1. Further, the Nyquist plot of the impedance is given for the low and higher Nd3+ samples and a simple model is proposed to fit the results. •NaBa(2-x)Nd2x/3Nb5O15 ceramics prepared by the conventional solid-state reaction techniques.•X-ray study has allowed identifying the stabilization of tetragonal Tungsten Bronzes structure.•Dielectric behavior change from normal ferroelectric to a relaxor one with the increasing Neodymium amount.•The complex impedance spectroscopy highlighted a thermally activated relaxation process in studied samples.