Combining Solid-State Shear Milling and FFF 3D-Printing Strategy to Fabricate High-Performance Biomimetic Wearable Fish-Scale PVDF-Based Piezoelectric Energy Harvesters

Abstract

High-performance flexible piezoelectric polymer− ceramic composites are in high demand for increasing wearable energy-harvesting applications. In this work, a strategy combining solid-state shear milling (S 3 M) and fused filament fabrication (FFF) 3D-printing technology is proposed for the fabrication of high-performance biomimetic wearable piezoelectric poly-(vinylidene fluoride) (PVDF)/tetraphenylphosphonium chloride (TPPC)/barium titanate (BaTiO 3 ) nanocomposite energy harvesters with a biomimetic fish-scale-like metamaterial. The S 3 M technology could greatly improve the dispersion of BaTiO 3 submicrometer particles and the interfacial compatibility, resulting in better processability and piezoelectric performance of the nanocomposites. Typically, the FFF 3D printed energy harvester incorporating 30 wt % BaTiO 3 showed the highest piezoelectric outputs with an open-circuit voltage of 11.5 V and a short-circuit current of 220 nA. It could hence drive nine green LEDs to work normally. In addition, a 3D-printed biomimetic wearable energy harvester inspired by an environmentally adaptive fish-scale-like metamaterial was further fabricated. The fish-scale-like energy harvester could harvest energy through different deformation motions and successfully recharge a 4.7 μF capacitor by being mounted on a bicycle tire and the tire's rolling. This work not only provides a 3D printing strategy for designing diversified and complex geometric structures but also paves the way for further applications in flexible, wearable, self-powered electromechanical energy harvesters.

Origami Tribo-Metamaterials with Mechanoelectrical Multistability

“…Mechanical metamaterials are the structural materials periodically assembled by microstructures to exhibit extraordinary mechanical characteristics, , which can be characterized between natural materials that are based on the intrinsic properties of materials and manmade structures that are mainly affected by structural properties. , As a consequence, the localized behavior of mechanical metamaterials at the microstructure level is structure-like, and the overall performance at the metamaterial level is similar to homogenized materials. , Mechanical metamaterials can overcome the trade-off challenge that natural materials typically have to face between physical properties and mechanical performance, such as origami metamaterials reported with bistable force–displacement relations . Since origami metamaterials are significantly dependent on their origami cells, well tunability over mechanical properties can be induced by rationally designing those cells. , Studies have been conducted on designing origami cells to obtain the origami metamaterials with desirable configurations, − unprecedented mechanical properties, such as negative Poisson’s ratio, − negative stiffness, , and advanced functions. , Recent research interests have been shifted to exploring the functionality of mechanical metamaterials using functional materials, such as energy materials for energy generation, power absorption, , energy storage, thermal materials for thermophotovoltaic response, thermomechanical response and thermoelastic response, , magnetic materials for electromagnetic energy harvesting and absorption, − and so forth. Recent development of advanced functional materials (e.g., self-healable materials, , nanomaterials, , etc.)…”

Degradable flexible piezoelectric nanogenerator based on two-dimensional barium titanate nanosheets and polylactic acid

“…For example, high-performance PNGs have been fabricated from polymer matrices, such as polyvinylidene fluoride (PVDF), polydimethylsiloxane (PDMS), and polylactic acid (PLA), embedded with lead zirconate titanate (PZT) and potassium sodium niobate (KNN) fillers. 12–14…”

“…For example, high-performance PNGs have been fabricated from polymer matrices, such as polyvinylidene fluoride (PVDF), polydimethylsiloxane (PDMS), and polylactic acid (PLA), embedded with lead zirconate titanate (PZT) and potassium sodium niobate (KNN) fillers. [12][13][14] Nanocomposites integrate the desirable properties of different materials and combine the flexibility of polymers with the electrical/mechanical properties of ceramics to meet specific device or application requirements. 15 Through the use of relatively stiff, mechanically robust ceramics and relatively flexible, lightweight polymers, nanocomposites can be designed to exhibit strength and flexibility.…”

Metal–Organic Framework–Derived ZnO‐Assisted β‐Phase‐Stabilized High‐Performance PVDF/ZnO‐PDMS/rGO Nanocomposites as Piezo–Tribo Hybrid Nanogenerator

“…Thus, MOF‐derived oxides interact more chemically with the polyvinylidene fluoride (PVDF) polymer matrix, resulting β ‐phase stabilization of PVDF. [ 24 ] Among several piezoelectric polymers, PVDF was the most useful piezoelectric flexible polymer [ 25 ] for its high piezoelectric charge coefficient, good breakdown strength, process ability, and lightweight electro‐active and long‐term stability. The β ‐phase of the polymer can be stabilized through doping of external fillers which is responsible for high piezoelectric properties.…”