Piezoelectric performance improvement via macromolecular rearrangement

Abstract

Because of their good flexibility and capacity to capture the dynamic mechanical energy by converting it into electrical signals, polymeric piezoelectric nanogenerators (PENGs) have broad application prospects in mechanical vibration detection and acquisition as sensors and self-powered systems. Here, a flexible PENG film based on hydroxypropyl cellulose (HPC) as the matrix, polyvinylidene fluoride (PVDF) as an auxiliary electrospinning reagent and BaTiO3 (BTO) nanoparticles (NPs) as a piezoelectric nanofiller is constructed by electrospinning and post-treatments for macromolecule rearrangement and thus piezoelectricity enhancement. This PENG demonstrates a superior sensitivity (23.33 mV kPa-1) which is over 3.9 times those of the commercial PVDF and PVDF-TrFE films. This performance enhancement is ascribed to the HPC dissolution and regeneration during post-treatments, resulting in the formation of outer wrappers around fibrils and thus an interconnected fibrous network with junction nodes between adjacent fibers for stress transfer efficiency. The partial crystal phase transformation of PVDF during film densification may also play a role in the increase of piezoelectricity. A series of practical application scenarios are established to demonstrate the highly promising potential of this fibril-based composite membrane for multifunctional force sensing and energy collection.

An electrospun cellulose-based nanofiber piezoelectric membrane with enhanced flexibility and pressure sensitivity

“…4d. This excellent sensitivity is superior to those of other recently reported piezoelectric composites and microstructures such as poly(vinylidene fluoride-trifluoroethylene) [P(VDF-TrFE)], 40 P(VDF-TrFE)/graphene oxide (GO) bi-layer, 40 P(VDF-TrFE) micropillar arrays, 41 P(VDF-TrFE)/boron nitride nanotube (BNNT) micropillar arrays, 41 a highly anisotropic piezoelectric network composite (HAPNC, consisting of the PZT ceramic network, PDMS, indium tin oxide (ITO) and polyethylene terephthalate (PET)), 42 and poly-(vinylidene fluoride- co -hexafluoropropylene) (PVDF-HFP)/Fe 3 O 4 (PHFe), 43 and biopolymer-based piezoelectric films made by electrospinning (hydroxypropyl cellulose/PVDF/BaTiO 3 44 ), casting (glycine–chitosan 45 or glycine–chitosan/ZnO 46 ) or gelation (ImClO 4 /bacterial cellulose hydrogel 47 ), as shown in Fig. 4e.…”

Study on Human Motion Energy Harvesting Devices: A Review

“…Since the turn of the century, piezoelectric materials have also been crucial components in ultrasonic motors, gyroscopes, aerospace technology, medical equipment, and optical instruments [91][92][93]. The advancement of integrated materials, low-energy electronic components, and piezoelectric materials has led to the maturation of piezoelectric vibration energy harvesting technology [94][95][96].…”