A PMNN‐PZT Piezoceramic Based Magneto‐Mechano‐Electric Coupled Energy Harvester.

It is desired to obtain a piezoceramic with a high piezoelectric coefficient and low dielectric loss simultaneously for energy harvester application. Herein, it is reported that the 0.025Pb(Mn1/3Nb2/3)O3‐0.525Pb(Ni1/3Nb2/3)O3‐0.135PbZrO3‐0.315PbTiO3 (PMNN‐PZT) ceramic exhibits superior piezoelectric charge parameter e33 of 37.74 pC m−2 and low dielectric loss tanδ of 0.45%. Furthermore, a PMNN‐PZT ceramic‐based magneto‐mechano‐electric coupled energy harvester (MMEC‐EH) with a varying‐stiffness cantilever is designed and fabricated, which shows the strong self‐resonance effect in response to a random, transient impulse vibration or magnetic field stimulus. The investigations show that under a 0.6 s pulse vibration stimulus, the MMEC‐EH can tune itself into self‐resonance damping oscillation lasting for six seconds at its resonance frequency of 16 Hz, and the produced maximum power is 1.96 mWRMS. Under both weak magnetic field and force‐field dual‐stimulus (Hac = 0.5 Oe and a = 0.05 g), the generated power density is about 60 mWRMS Oe−2g−2cm−3, which is one to two orders of magnitude higher than those previously reported MMEC‐EHs. Finally, the MMEC‐EH is successfully demonstrated to power temperature/humidity sensors, indicating its potential for harvesting both weak vibration and magnetic field energy from environments for self‐powered sensor application. [ABSTRACT FROM AUTHOR]