The high energy density of pb(Zr1-xTix)O3-pb(Ni1/3Nb2/3)O3 ceramics for piezoelectric energy harvesting devices

Abstract

The energy density of 0.65Pb(Zr1-xTix)-0.35Pb(Ni1/3Nb2/3)O3 [0.65P(Z1-xTx)-0.35PNN] ceramics has been investigated with respect to their structural variations. The 0.65P(Z1-xTx)-0.35PNN ceramic with x = 0.58 exhibited a morphotropic phase boundary (MPB), in which pseudo-cubic and tetragonal structures coexisted. The ε33T/ε0 value of the 0.65P(Z1-xTx)-0.35PNN ceramic decreased considerably on the pseudo-cubic side of the MPB composition, while the d33 slowly decreased on both sides of the MPB. Because the g33 is given by d33/ε33T, the maximum transduction coefficient (d33 × g33) was obtained from the composition on the pseudo-cubic side of the MPB. In particular, the 0.65P(Z0.45T0.55)-0.35PNN (0.65PZT55-0.35PNN) ceramic with a pseudo-cubic structure showed the maximum d33 × g33 value of 16,500 × 10-15 m2/N. Moreover, the 0.65PZT55-0.35PNN ceramics with 1.5 mol% CuO added were well sintered even at 950 °C, and also exhibited a high d33 × g33 value of 15,853 × 10-15 m2/N, indicating that the 0.65PZT55-0.35PNN ceramic with CuO added is a good candidate material for multilayer energy harvesting devices.