Highly durable piezoelectric energy harvester based on a PVDF flexible nanocomposite filled with oriented BaTi2O5 nanorods with high power density

摘要

Rapid developments in personal electronics and sensor networks have raised urgent and challenging requirements for portable and sustainable power sources. As a result, fabrication of highly durable piezoelectric energy harvesters with high power density has become a priority. In this work, a sensitive flexible piezoelectric energy harvester (FPEH) was constructed by filling a poly(vinylidene fluoride) (PVDF) polymer matrix with oriented BaTi2O5 nanorods (BT2). Synthesizing the BT2 nanorods by the molten salt method gave them a strong polarity along the b-axis, and they were then further aligned in the horizontal direction in the PVDF matrix by hot pressing, which helped to give them a textured structure that would ensure a significant increase in power generation in the cantilever beam mode. Out of all the compositions, 5 vol% BT2/PVDF FPEH exhibited the optimal energy harvesting performance with a high power density of 27.4 mu W/cm(3) together with excellent mechanical properties under a large acceleration of 10 g. More importantly, the FPEH retained its performance even after an extended period of cantilever vibration cycles (similar to 330,000). Because of their excellent performance, FPEHs show great potential for harvesting mechanical energy for self-powered systems and can be used to harvest energy from rotating wheels to charge a capacitor and instantly power up various sensors.