High-performance piezoelectric composite combined with PZT micropillars and P(VDF-TrFE) membrane for energy harvesting and sensing

Inorganic-organic piezoelectric composites with good mechanical flexibility and outstanding piezoelectricity are attractive in wearable/portable electronics. In this paper, a high-performance flexible piezoelectric composite based on micropillar array of PbZr0.52Ti0.48O3 (PZT) and P(VDF-TrFE) membrane is achieved for energy harvesting and sensing. By using anodized aluminum oxide templates, large-sized PZT micropillar array with regular distribution is prepared on well crystalline P(VDF-TrFE) platform. The composite piezoelectric device exhibits enhanced energy harvesting performance with output voltage of 2.7 V, and power of 4.4 mu W, which is 1.4 times and 2.2 times higher than that of the P(VDF-TrFE) composite films doped with PZT particles. Finite-element analysis shows that the vertically aligned pillars can generate a large strain, thus leading to an enhancement of the piezoelectric potential. Stable electric output signal can be generated whenever the device subjected to external bending or pressing stress, implying its capacity in sensing application. Moreover, it also can capture external mechanical energy from elementary body movement or detect external pressure over a low frequency range. This work opens up a promising route to develop piezoelectric microstructure composite applied in fields of wearable energy harvester and multifunctional sensors.