A technique for giant mechanical energy harvesting using ferroelectric/antiferroelectric materials

Ferroelectric materials are widely employed as piezoelectric materials for numerous energy harvesting systems. However, conventional systems employing direct piezoelectric effect for vibrational energy harvesting suffer from low energy density and high actuation frequency requirements. In this regards, the authors have presented a new technique for giant mechanical energy conversion using ferroelectric/antiferroelectric materials in a cyclic manner. The proposed method will allow for large electromechanical energy conversion in a wide frequency domain. The cycle was simulated for polycrystalline Pb0.99Nb0.02[(Zr0.57Sn0.43)(0.94)Ti-0.06](0.98)O-3 (PNZST) antiferroelectric bulk ceramic. It was observed that for cycle parameters of (20 to 60 kV.cm(-1) and 0 to 250 MPa), a harvesting energy density of 689 kJ.m(-3).cycle(-1) can be obtained for uniaxial compressive stress. While an energy density of 919 kJ.m(-3).cycle(-1) can be obtained for radial compressive stress with cycle parameters of (20 to 60 kV.cm(-1) and 0 to 360 MPa). This is several orders of magnitude larger than the highest energy density reported in the literature. (C) 2014 AIP Publishing LLC.