Ultrathin Biocompatible Electrospun Fiber Films for Self-Powered Human Motion Sensor

Jin

ACS Appl. Electron. Mater.

et al. 2021

As a new branch of energy conversion technology, the triboelectric nanogenerator (TENG) can effectively convert mechanical energy into electrical energy and realize a self-driving system. As one of the most important indexes of TENG, charge density determines the performance of TENG. In this Review, two aspects of increasing charge density and reducing charge loss are discussed. In terms of increasing the charge density, material selection is the most fundamental, which determines the initial amount of transferred charge; increasing the contact area is the most commonly used; larger contact area can accumulate more charge; improving the internal or dipole arrangement of materials is the most easily overlooked link. At the same time, retaining the obtained charge and reducing the charge loss is also an important way to improve the performance of TENG. Aiming at the problems of high voltage, low current, and charge loss caused by TENG's impedance matching, this Review summarizes the direct current conversion, buck conversion, and energy storage. Finally, we summarize and discuss the previous results and make a prospect for the future development trend of TENG.

Section: Increasing Charge Densitymentioning

confidence: 99%

Efficient Triboelectric Nanogenerator (TENG) Output Management for Improving Charge Density and Reducing Charge Loss

Jin

ACS Appl. Electron. Mater.

et al. 2021

“…[158] It is known that the modifications of material surface through morphology and functionalization, choice of the triboelectric pairs, and thickness of the material influence the surface charge density. [108,[159][160][161][162][163] Creating micro/nanostructures on the material surface contributes to the increase of surface charge density by extending the triboelectric contact area on the surface. Polymeric triboelectric material has an internal porous structure, charges are not only generated on the surface but also induced in the interior of the pores.…”

Section: Triboelectric Materials Used In Ngsmentioning

confidence: 99%

“…In addition to PVDF and its copolymers, PAN (polyacrylonitrile), PVA (poly(vinyl alcohol), PDMS, PU, PLLA, PTFE (polytetrafluoroethylene), PMMA (poly(methyl methacrylate)), polyimide (PI), PA6, silk fibroin, and ethyl cellulose have also been reported for the fabrication of nanofiber-based wearable TENGs. [163,[185][186][187][188][189][190][191] Jiang et al have prepared an all-electrospun flexible TENG using PVA fiber doped with electronegative MXene nanosheets as a negative friction layer and silk nanofibers as a positive friction layer. [187] Proposed TENG can be used for both energy harvesting and real-time monitoring of body movement.…”

Section: Electrospun Fiber-based Tengsmentioning

confidence: 99%

Advances in Electrospun Fiber‐Based Flexible Nanogenerators for Wearable Applications

Arıca

Işık²,

Güner

et al. 2021

Macro Materials & Eng

In today's digital age, the need and interest in personal and portable electronics shows a dramatic growth trend in daily life parallel to the developments in sensors technologies and the internet. Wearable electronics that can be attached to clothing, accessories, and the human body are one of the most promising subfields. The energy requirement for the devices considering the reduction in device sizes and the necessity of being flexible and light, the existing batteries are insufficient and nanogenerators have been recognized a suitable energy source in the last decade. The mechanical energy created by the daily activities of the human body is an accessible and natural energy source for nanogenerators. Fiber‐structured functional materials contribute to the increase in energy efficiency due to their effective surface to volume ratio while providing the necessary compatibility and comfort for the movements in daily life with its flexibility and lightness. Among the potential solutions, electrospinning stands out as a promising technique that can meet these requirements, allowing for simple, versatile, and continuous fabrication. Herein, wearable electronics and their future potential, electrospinning, and its place in energy applications are overviewed. Moreover, piezoelectric, triboelectric, and hybrid nanogenerators fabricated or associated with electrospun fibrous materials are presented.

“…[1][2][3][4][5][6][7] Inspired by the triboelectric effect between clothes during human movement, many studies have achieved energy conversion and biosensing by integrating triboelectric nanogenerators (TENGs) into the fabrics that humans wear or by attaching TENG units to human bodies. [8][9][10][11][12][13][14] However, the materials used in the majority of studies were not only complex but also expensive. As a result, choosing natural triboelectric materials is a feasible idea for lowering the cost and processing difficulty of TENGs.…”

Section: Introductionmentioning

confidence: 99%

Wearable Electronics Powered by Triboelectrification between Hair and Cloth for Monitoring Body Motions

et al. 2022

Diverse triboelectric nanogenerators (TENGs) have been extensively applied in self‐powered wearable electronics. The TENG‐based demonstration using the human body as a triboelectric material is rare, though wearable electronics plays a more and more pivotal role in portable intelligent medicine. Human hair, as part of the human body, can be a component of a TENG‐based wearable system. Herein, a novel body‐based TENG configuration made of human hair and polydimethylsiloxane (PDMS)‐coated carbon cloth is proposed. Due to triboelectrification between the hair and the PDMS layer, the output voltage can deliver 1.713 and 0.377 V in the vertical contact‐separation mode and sliding mode, respectively. In addition, a self‐powered application based on the hair‐based TENG for actively monitoring the motion state by comparing the amplitude and frequency of the output voltages is successfully demonstrated. This study broadens the application of body‐based TENGs and provides a promising and feasible strategy for developing smart health monitoring.