Search

This paper explores the feasibility of utilizing lead-free multilayer piezo stacks, particularly focusing on Zr-doped 0.95(Bi 0. 5 Na 0.5)TiO 3 -0.05(BaTiO 3) piezoceramics, for energy harvesting. Various lead-free BNT-BT disk samples with different Zr concentrations undergo structural, microstructural, and electrical characterizations. The results illustrate that Zr-doping improves piezoelectric constitutive parameters, notably at a 2.0 mol% concentration. Electromechanical tests were conducted on multilayer piezo stacks, involving variations in electric load, mechanical load, frequency, and number of stacked disks. These tests demonstrate the ability of the multilayer transducer to produce up to 1.5 V (peak) under particular conditions: a 250 Hz frequency, a 10 N mechanical load, and an open circuit electric load, utilizing a stack comprising 5 disks. Employing an analytical mathematical model, an effective d 33 e f f of the system is determined, yielding values ranging from 588 to 625 pC/N for a stack composed of 5 disks. These findings highlight the considerable potential of lead-free multilayer piezo stacks in energy harvesting applications, offering crucial insights for the development of sustainable and eco-friendly energy solutions. [ABSTRACT FROM AUTHOR]

In this work, we report the harvested energy of lead-free 0.94(Bi 0.5 Na 0.5)TiO 3 -0.06BaTiO 3 bulk ceramics using two different geometries (rectangular plate and disk). These ceramics were obtained by the solid-state reaction method and their good ferroelectric properties were reported. The samples were characterized using X-ray diffraction (XRD), Raman microspectroscopy and Scanning Electron Microscopy (SEM) analysis, whereas ferroelectric and dielectric properties were evaluated by means of ferroelectric hysteresis loops and impedance spectroscopy studies. A cantilever-based harvester was proposed to evaluate the performance of Piezoelectric Energy Harvesting (PEH). The morphological influence on the voltage generation was experimentally and numerically studied by the Finite Element Method (FEM). Several cases for plate and disk-shaped piezoelectric ceramics were simulated under a constant volume restriction. Results showed a great influence of the morphology on the electromechanical response of the system. In particular, the plate featured a higher voltage generation than the disk. [ABSTRACT FROM AUTHOR]