Hybrid fibrous (PVDF-BaTiO₃)/ PA-11 piezoelectric patch as an energy harvester for pacemakers

Abstract

Lithium batteries have been widely used to power up implantable medical devices such as pacemakers that are often designed to treat, diagnose, and prevent different diseases. However, due to their limited capacity and lifetime, patients have to undergo a surgical procedure to replace the discharged battery. Recently, nanogenerators have been emerged and are broadly accepted since they can convert tiny biomechanical forces, such as heartbeats, into electrical energy. This study aims to manufacture a biocompatible and high-performance piezoelectric energy harvester (PEH) that is capable to be charged by the energy received from the heartbeat and store the generated voltage. In this research, a hybrid structure of poly (vinylidene fluoride) (PVDF) coupling with polyamide-11 (PA-11) was fabricated using dual electrospinning to enhance the piezoelectric properties of the intended PEH. The piezoelectric test results show an acceptable increase in nanofibers’ piezoelectric sensitivity from 62.87 mV/N to 75.75 mV/N by adding 25% (v/v) of PA-11 to PVDF, indicating the synergistic effect of PVDF and PA-11. The specimen PVDF (75% v/v)-PA-11 (25% v/v) also showed the highest mechanical strength and consequently is suggested as the optimum sample. To further enhance the efficacy and sensitivity of PEH to convert the small mechanical forces into an acceptable voltage, 15% (w/w) of barium titanate (BaTiO3) nanoparticles were added to the hybrid structure. The crystallinity and mechanical strength were noticeably increased by incorporating BaTiO3 nanoparticles into the fibrous structure, leading to a piezoelectric sensitivity of 107.52 mV/N. This result lays the groundwork for producing an effective piezoelectric patch that could be used as pacemaker batteries.

Full and In Situ Printing of Nanogenerators that Are Based on an Inherently Viscous Piezoelectric Polymer: An Effort to Minimize “Coffee Ring Effect” and Nonprinting Operations

“…Pure PVDF was used in this work. Even though some PVDF nanocomposites, in which one or more piezoelectric fillers (such as lead zirconate titanate (PZT), zinc oxide, , and barium titanate) or nonpiezoelectric fillers (such as carbon nanotubes , and reduced graphene oxide) are incorporated into a PVDF matrix, have enhanced piezoelectric performance, pure PVDF has the following advantages over its nanocomposite counterparts: (1) Pure PVDF exhibits much better flexibility, which makes it more durable as the piezoelectric component of a device that works via cyclic bending and unbending. (2) Pure PVDF is superior in biocompatibility, long-term stability, light weight, and excellent resistance to chemical corrosion, which makes it more suitable for medical textile applications and fabricating self-powered wearable electronics that can harvest energy from animal/human bodies.…”

A Review on Wearable Electrospun Polymeric Piezoelectric Sensors and Energy Harvesters

“…The piezoelectric response of amorphous polymers is generally lower than that of semicrystalline polymers. To date, a variety of piezoelectric polymers have been reported, such as PVDF, [3][4][5][6][7][8]20,33,35,36,39,42] PVDF copolymers, [3,4,[6][7][8]20,36] PAN, [6,36] polylactic acid (PLA), [5,65] polypropylene (PP), [6,20,36] polyamide 11 (PA11 or Nylon 11), [6,20,35,36,42,66] polyureas, [6,35,42] polyurethane, [67] biopolymers (e.g., cellulose), [35,42,68] and liquid crystalline polymers. [42] This section will introduce briefly the key characteristics of these different types of piezoelectric polymers.…”

Enhanced Piezoelectricity of PVDF-TrFE Nanofibers by Intercalating with Electrosprayed BaTiO3

“…As compared to PVDF, PVDF-TrFE is known to exhibit higher piezoelectric properties due to higher β-phase content and crystallinity. It also offers improved biocompatibility due to the addition of TrFE, which increases hydrophilicity. ,,, Moreover, BTO is reported to have a higher piezoelectric coefficient than ZnO . These superior properties are expected to expand their applications.…”

“…14,25,28,34 Moreover, BTO is reported to have a higher piezoelectric coefficient than ZnO. 35 These superior properties are expected to expand their applications. The piezoelectricity of the layered PVDF-TrFE + BTO nanofiber mats with BTO electrosprayed between PVDF-TrFE nanofiber layers was studied and compared with those with BTO uniformly dispersed into PVDF-TrFE nanofibers.…”