Improving the functional properties of (K0.5Na0.5)NbO3 piezoceramics by acceptor doping

ZrO2 and TiO2 modified lead-free (K0.5Na0.5)NbO3 (KNN) piezoelectric ceramics are prepared by conventional solid-state reaction. The effect of acceptor doping on structural and functional properties are investigated. A decrease in the Curie temperature and an increase in the dielectric constant valu...

Descripción completa

Detalles Bibliográficos
Autores: Vendrell, Xavier, García García, José Eduardo, Bril, X., Ochoa Guerrero, Diego A., Mestres i Vila, Ma. Lourdes, Dezanneau, Guilhem
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2015
País:España
Institución:Varias* (Consorci de Biblioteques Universitáries de Catalunya, Centre de Serveis Científics i Acadèmics de Catalunya)
Repositorio:Recercat. Dipósit de la Recerca de Catalunya
OAI Identifier:oai:recercat.cat:2445/128547
Acceso en línea:https://hdl.handle.net/2445/128547
Access Level:acceso abierto
Palabra clave:Piezoelectricitat
Ceràmiques electròniques
Química de l'estat sòlid
Plom
Piezoelectricity
Electronic ceramics
Solid state chemistry
Lead
Descripción
Sumario:ZrO2 and TiO2 modified lead-free (K0.5Na0.5)NbO3 (KNN) piezoelectric ceramics are prepared by conventional solid-state reaction. The effect of acceptor doping on structural and functional properties are investigated. A decrease in the Curie temperature and an increase in the dielectric constant values are observed when doping. More interestingly, an increase in the coercive field Ec and remanent polarization Pr is observed. The piezoelectric properties are greatly increased when doping with small concentrations dopants. ZrO2 doped ceramic exhibits good piezoelectric properties with piezoelectric coefficient d33=134 pC/N and electromechanical coupling factor kp=35%. It is verified that nonlinearity is significantly reduced. Thus, the creation of complex defects capable of pinning the domain wall motion is enhanced with doping, probably due to by the formation of oxygen vacancies. These results strongly suggest that compositional engineering using low concentrations of acceptor doping is a good means of improving the functional properties of KNN lead-free piezoceramic system.