Enhancing electrical properties in KNN based high-entropy piezoelectric ceramics by optimizing sintering temperature

The development of high electrical performance (K,Na)NbO3 (KNN)-based piezoelectric ceramics is critical in environmental protection. In this study, (K0.5Na0.5)(Ti0.2Zr0.2Nb0.2Ta0.2Sb0.2)O3 high-entropy ceramics were synthesized via the solid solution method by different sintering temperature. The piezoelectric, dielectric and ferroelectric properties of (K0.5Na0.5)(Ti0.2Zr0.2Nb0.2Ta0.2Sb0.2)O3 ceramics were studied. The sample sintered at 990 degrees C has the best dielectric property, and the dielectric constant is stable in a wide temperature region. The sample sintered at 980 degrees C have the highest porcelain forming property, the residual polarization intensity is 0.0792 mu C/cm2, the activation energies obtained is 0.40 eV. The results confirm that the calcined at 980 degrees C (K0.5Na0.5)(Ti0.2Zr0.2Nb0.2Ta0.2Sb0.2)O3 ceramics is feasible in the field of electrical application. This work proves a design idea to obtain high electrical performance in KNN-based high-entropy ceramics via composition design by optimizing sintering temperature.