Crystal structure and electrical properties of AgNbO3-based lead-free ceramics

摘要

Lead-free perovskite ceramics (1-x)(Ag0.96Na0.04)NbO3-xKNbO(3) (x=0.00 similar to 0.10) are synthesized via the solid state reaction method in flowing O-2 and the evolution of structure and electrical properties with K content have been investigated. X-ray diffraction reveals that a phase transition occurs from the virgin antiferroelectric-like state to ferroelectric phase at x=0.04. For the compositions x <= 0.04, the dielectric properties show that the phase transition temperatures of M-1-M-2, M-2-M-3 and M-3-O-1 shift to a lower temperature as the K-doping level increases. The compositions x < 0.04 display double hysteresis loops with an increase of remanent polarization P-r with increasing K concentration. The polarization hysteresis loops are also evaluated to verify the temperature-induced M-1-M-2 phase transition at temperature up to 120 degrees C for the composition x=0.04. (C) 2016 Elsevier Ltd and Techna Group S.r.l. All rights reserved.