Ferroelectric and dielectric properties of KF-added (K0.48Na0.52)NbO3lead-free ceramics

• Published in: Physica. B, Condensed matter Vol. 564; pp. 28 - 32
• Main Authors: Huang, Hui-shun, Chen, Xiao-ming, Lu, Jiang-bo, Lian, Han-li
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 01.07.2019; Elsevier BV
• Subjects: Ceramics; Coercivity; Conductivity; Dielectric properties; Electrical properties; Ferroelectric materials; Ferroelectric properties; Ferroelectricity; Microstructure; Niobates; Piezoelectricity; Point defects; Polarization; Potassium sodium niobate; Scanning probe microscopes; Potassium sodium niobate; Ceramics; Ferroelectric properties; Dielectric properties
• ISSN: 0921-4526; 1873-2135
• DOI: 10.1016/j.physb.2019.04.010

Pure (K0.48Na0.52)NbO3 and (K0.48Na0.52)NbO3-2%mol KF (abbreviated as KNN and KNN-KF, respectively) ceramics were synthesized by means of solid-state sintering. Ferroelectric and dielectric properties of KNN and KNN-KF were investigated comparatively. Microscopic electrical performance of KNN-KF was detected via a scanning probe microscope. For KNN, piezoelectric constant (d33) is 80 pC/N, coercive field (Ec) is 21.9 kV/cm, maximum polarization (Pm) is 12.6 μC/cm2, remanent polarization (Pr) is 10.0 μC/cm2. For KNN-KF, the corresponding values are d33 = 105 pC/N, Ec = 16.0 kV/cm, Pm = 27.3 μC/cm2, and Pr = 21.6 μC/cm2. The enhancement of electrical properties for KNN-KF was discussed according to its microstructure and effect of point defects. •KNN-KF exhibits Pr = 21.6 μC/cm2, Ec = 16.0 kV/cm, d33 = 105 pC/N, εr = 496, d33 = 105 pC/N.•PFM reveals easy switching of domains in KNN-KF with changing E on microscale.•Enhanced electrical properties are related to dense microstructure and reduced point defects.