Significantly Enhanced Transduction Coefficient of PLZT Ceramics to Obtain a Very High Power Density as a Piezoelectric Energy Harvester

Piezoelectric energy harvesters (PEHs) have attracted much attention due to their efficient harvesting of vibrational energy from the ambient environment, which demonstrates great potential applications. Unfortunately, their low energy density severely hinders the further development of PEHs. Therefore, it is highly desirable to search for piezoelectric materials with a high transduction coefficient (d₃₃ × g₃₃). In this work, an excellent d₃₃ × g₃₃ is achieved in Pb_0.94(La_0.06-xNd_x) (Zr_0.58Ti_0.42)_0.985O₃ (x = 0, 0.01, 0.02, 0.03, and 0.04) (PL_0.06-xN_xZT) ceramics by composition modulation. The best d₃₃ × g₃₃ of 26.71 pm²/N is obtained with an optimal composition of x = 0.02. Moreover, a superior output voltage of 28.4V_p and power density of 15.93 μW/mm³ are simultaneously obtained for the sample applied in the PEH system. The sizes of the polar nanodomains of the samples are estimated using a phenomenological statistical model, and the domain configuration is observed using PFM. Our results indicate that composition modulation in PLZT can regulate and awaken ferroelectric domains, giving rise to an ultrahigh d₃₃ × g₃₃, which consequently results in enhanced performance of the output voltage and power density of PEHs.