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


Author to whom correspondence should be addressed. e-mail: snahm@korea.ac.kr


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.