Ultrahigh augmentation of flexible composite-based piezoelectric energy harvesting efficiency via polymer-impregnated nanoparticles network within 3D cellulose scaffold

In the past decade, many flexible piezoelectric energy harvesters (PEHs) that can convert ambient mechanical energy into electrical energy have been developed, which provides a sustainable power source for wearable/implantable devices and Internet of Things (IoTs) applications. However, the performance of flexible composite-type PEHs should be further optimized to meet the standard for future practical applications. Herein, we present a powerful strategy for high-performance piezoelectric energy harvesting with poly(vinylidenefluoride-co-trifluoroethylene) (P(VDF-TrFE))-impregnated BaTiO3 nanoparticles network within 3-dimensional (3D) cellulose scaffold. We propose three methodologies to precisely adjust the microscopic morphology of the organic-inorganic hybrid piezoelectric composites. The construction of methyl cellulose scaffold results in effective stress transfer with high mechanical flexibility as well as dramatically enhanced energy harvesting output. When the cellulose content is 3 wt%, the optimal energy harvesting performance is obtained, which shows the power density of 42 mu W/cm3, which is nearly 800% higher than that of the conventional flexible piezoelectric composites previously reported. Throughout the finite-element simulation and mechanical property quantification, the highly augmented energy harvesting capability of our optimal composite structure is determined to stem from the stress-enforced characteristics. Given the ease of fabrication and scalability, this work opens up the way for the development of flexible and high-performance energy harvesting applications.

Automated summary

In the past decade, flexible piezoelectric energy harvesters (PEHs) have been developed to convert ambient mechanical energy into electrical energy, providing sustainable power source for wearable/implantable devices and Internet of Things (IoTs) applications. However, the performance of flexible composite-type PEHs needs further optimization to meet future practical applications. This study presents a powerful strategy for high-performance piezoelectric energy harvesting using 3D cellulose scaffold impregnated with poly(vinylidenefluoride-co-trifluoroethylene) (P(VDF-TrFE))-impregnated BaTiO3 nanoparticles network. Three methodologies are proposed to adjust the microscopic morphology of the organic-inorganic hybrid piezoelectric composites, resulting in enhanced energy harvesting output. The optimal energy harvesting performance is achieved when the cellulose content is 3 wt%, showing a power density nearly 800% higher than that of conventional flexible piezoelectric composites previously reported, attributed to the stress-enforced characteristics of the optimal composite structure.