1Department of Material Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333001
2Department of Applied Physics and Materials Research Center, The Hong Kong Polytechnic University, Hong Kong
3State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050
Water-Induced Degradation in Lead Zinc Niobate--Lead Zirconate Titanate Soft Piezoelectric Ceramics
1Department of Material Science and Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333001
2Department of Applied Physics and Materials Research Center, The Hong Kong Polytechnic University, Hong Kong
3State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 200050
Abstract： Water-induced degradation of lead zinc niobate--lead zirconate titanate (Pb(Zn1/3Nb2/3)O3-Pb(ZrTi)O3) soft piezoelectric ceramics is studied using electrochemical hydrogen charging, in which the silver electrodes of the piezoelectric ceramics constitute a cathode in 0.01-M NaOH solution to evolve hydrogen by electrolysis of water. It is found that with the increasing hydrogen charging time, the resonance impedance increases, the difference between the resonance frequency and the anti-resonance frequency decreases, the spontaneous polarization, the remanent polarization and the piezoelectric coefficient d33 decrease. The degradation behaviour of the soft piezoelectric ceramics can be explained to hydrogen incorporating into the lattice and forming hydroxy (OH-) bonds in the perovskite structure, which prevents the Ti ions from switching and increases the coercive field Ec. The degradation characteristics of the soft piezoelectric ceramics are quite different from that of lead zirconate titanate hard piezoelectric ceramics.
2005, Vol. 22 
