Piezoelectric Properties of Lead‐free Piezoelectric Ceramics and Their Energy Harvester Characteristics

Abstract

The energy convergence efficiency (η) and dimensionless figure of merit (DFOM) of CuO‐added (Na0.5K0.5)NbO3 (CNKN) ceramics are larger than those of NKN ceramics because of their large Qm values and small dielectric losses. Moreover, the η and DFOM values of CNKN ceramics are comparable to those of P‐5C ceramics, which exhibit the highest η and DFOM. Furthermore, the CNKN harvester exhibits a high power density of 12 mW/cm3 at 93 Hz with a load resistance of 250 kΩ; this is similar to the PZT‐based energy harvester, indicating that the CNKN ceramic is a good candidate material for energy harvesters.