Piezoelectricity of (K,Na)(Nb,Sb)O₃–SrZrO₃(Bi,Ag)ZrO₃piezoceramics and their application in planar-type actuators

Abstract

The KNNS–0.01SZ–0.03BAZ piezoceramic exhibited a large d33 of 650 pC/N because of the presence of a TE–O–R multi-structure and nanodomains. A planar-type KNNS–0.01SZ–0.03BAZ thick-film actuator showed excellent actuating properties.

Crystallographic texture and phase structure induced excellent piezoelectric performance in KNN‐based ceramics

“…Based on this strategy, a series of breakthroughs have been made in KNN-based ceramics over the last decade. [14][15][16][17][18] For a few examples, piezoelectric coefficients (d 33 ) of 525 and 650 ± 20 pC/N were successively achieved at the PPB composition in KNNS-BNKH and KNNS-BNKZ-Fe-AS systems, respectively, which are comparable to those of commercial PZT ceramics. 16,17 The excellent piezoelectric properties have been verified to originate from the flattening energy barrier induced by PPB, benefiting the polarization reversal.…”

“…The PPB can be successfully constructed at approximately room temperature by elevating the phase transition temperature between the rhombohedral (R) and orthorhombic (O) phases, and simultaneously decreasing the phase transition temperature between the orthorhombic and tetragonal (T) phases. Based on this strategy, a series of breakthroughs have been made in KNN‐based ceramics over the last decade 14–18 . For a few examples, piezoelectric coefficients ( d 33 ) of 525 and 650 ± 20 pC/N were successively achieved at the PPB composition in KNNS–BNKH and KNNS–BNKZ–Fe–AS systems, respectively, which are comparable to those of commercial PZT ceramics 16,17 .…”

Ultrahigh Performance Piezoelectric Energy Harvester Using Lead-Free Piezoceramics with Large Electromechanical Coupling Factor

“…However, because their piezoelectricity is still low, several studies have attempted to enhance it. The formation of polymorphic phase boundary (PPB) structures such as tetragonal-orthorhombic (T-O), orthorhombic-rhombohedral (O-R), T-R, and T-O-R structures has been used to enhance the piezoelectricity of KNN-related piezoceramics [15][16][17][18][19][20][21][22]. Particularly, the KNN-related piezoceramics with an ideal T-O-R structure, where each structure has an identical proportion of approximately 33%, have been reported to show a very large d 33 value [20][21][22].…”

“…The formation of polymorphic phase boundary (PPB) structures such as tetragonal-orthorhombic (T-O), orthorhombic-rhombohedral (O-R), T-R, and T-O-R structures has been used to enhance the piezoelectricity of KNN-related piezoceramics [15][16][17][18][19][20][21][22]. Particularly, the KNN-related piezoceramics with an ideal T-O-R structure, where each structure has an identical proportion of approximately 33%, have been reported to show a very large d 33 value [20][21][22]. However, as the ε T ij value of KNN-related piezoceramics with the ideal T-O-R structure is generally large, their k ij and d ij × g ij values are relatively low [20][21][22].…”

“…Particularly, the KNN-related piezoceramics with an ideal T-O-R structure, where each structure has an identical proportion of approximately 33%, have been reported to show a very large d 33 value [20][21][22]. However, as the ε T ij value of KNN-related piezoceramics with the ideal T-O-R structure is generally large, their k ij and d ij × g ij values are relatively low [20][21][22]. Therefore, the formation of the PPB structure is not an effective approach to developing KNN-related piezoelectric ceramics for PEH.…”