Large enhancement of transduction coefficient in PZN-PZT energy harvesting system through introducing low-epsilon(r) PIN relaxor

摘要

Designing piezoceramics with a large transduction coefficient (d(33) x g(33)) is key to improving the power generation of piezoelectric energy harvesters (PEHs). However, in popular PEH materials such as Pb(Zn1/3Nb2/3)O-3-Pb(Zr1/2Ti1/2)O-3 (PZN-PZT), the same trend in the variation of d(33) and epsilon(r) makes it difficult to achieve a large d(33) x g(33). In this work, we introduced low-epsilon(r) Pb(In1/2Nb1/2)O-3 (PIN) into the PZN-PZT matrix to pull down the epsilon(r) of the quaternary system. This simultaneously stabilized d(33) in a certain range due to the refinement of the domain structure and increased the electrostrictive coefficient (Q(33)), and consequently the d(33) x g(33) value increased to 16081 x 10(-15) m(2)/N for the optimal composition. We assembled a cantilever beam type PEH from the preferred material with a power density up to 3.37 mu W/mm(3) at 1 g acceleration, and demonstrated its use to charge an electrolytic capacitor to drive commercial blue LEDs and a speed sensor.