Physical properties of the new ceramics in the mixed oxide system Na_1−xLi_xNb_1−xSb_xO₃

Chiheb Chaker (1) , Walid El Gharbi (1) , Najmeddine Abdelmoula (1) , Hamadi Khemakhem (1) , Annie Simon (2) , Mario Maglione (2)

1 LMF - Laboratoire des Matériaux Ferroélectriques
2 ICMCB - Institut de Chimie de la Matière Condensée de Bordeaux

New ferroelectric or relaxor ceramics with composition Na_1−xLi_xNb_1−xSb_xO₃ (0.05 ≤ x ≤ 0.30) were elaborated and sintered in the temperature range 1100–1200 °C. The effect of cationic substitution of the sodium with the lithium in the A site and the niobium with the antimony in the B site in the NaNbO₃ perovskite lattice on physical properties were investigated. X-ray diffraction at room temperature and dielectric permittivity in the temperature range from 200 to 500 K with frequencies from 0.1 to 200 kHz characterisations were used. X-ray diffraction analysis demonstrates that all samples have a single phase with quadratic perovskite structure. Dielectric measurements show that the material have a classical ferroelectric behaviour for 0 < x ≤ 0.15 and a relaxor one for 0.20 ≤ x ≤ 0.30. The polarisation state was checked by pyroelectric and piezoelectric measurements. For x = 0.20, the piezoelectric coefficient d₃₁ is of 15.3 pC/N.

Mots clés: Ceramics; Ferroelectric; Relaxor; X-ray diffraction; Pyroelectric and piezoelectric

Domaines: Matériaux

Chiheb Chaker, Walid El Gharbi, Najmeddine Abdelmoula, Hamadi Khemakhem, Annie Simon, et al.. Physical properties of the new ceramics in the mixed oxide system Na_1−xLi_xNb_1−xSb_xO₃. Journal of Alloys and Compounds, 2009, 481 (1-2), pp.305-309. ⟨10.1016/j.jallcom.2009.03.032⟩. ⟨hal-00414552⟩