Electromagnetic Shielding Hybrid Nanogenerator for Health Monitoring and Protection

Abstract

Nowadays, mankind faces increasingly energy crisis and electromagnetic radiation pollution. An energy harvester with function of protecting human health from electromagnetic radiation is a desirable solution to this problem. Here, a stretchable electromagnetic shielding hybrid nanogenerator (ES-HNG) is reported which can not only scavenge thermal and mechanical energy from living environment but also protect and monitor human health. The ES-HNG is capable of transforming mechanical and thermal energy to electricity based on triboelectric, piezoelectric, and pyroelectric effects. To be devised as a computer keyboard cover, ES-HNG takes about 200 s to charge a capacitor to 3 V by typing. The stored energy can drive the portable devices successfully. Besides, the ES-HNG eliminates electromagnetic radiation of computer completely due to its unique electromagnetic shielding property. A large range of electromagnetic wave (frequency is between 0 and 1.5 GHz) is shielded more than 99.9978% by the ES-HNG. Moreover, the ES-HNG is able to monitor human health by attaching it on human abdomen to be a self-powered sensor. This work opens up a new prospect of harvesting energy effectively as well as protecting/monitoring human health from electromagnetic radiation surroundings. as human motions, which plays an important role with respect to wearable electronics. [3][4][5][6][7][8][9] However, the power output from the TENG is not enough to actuate most of wearable electronics. Therefore, hybrid nanogenerators (HNGs) which integrate TENGs with other nanogenerators were developed to solve the problem of low output. The developed HNGs can simultaneously/individually scavenge the mechanical and thermal energy from the living environment efficiently. [10][11][12][13][14] As a crucial candidate to a part of HNG, pyroelectric-piezoelectric nanogenerator (PPENG) which based on poly(vinylidene fluoride) (PVDF) scavenges thermal energy with a temperature gradient and mechanical energy from environment efficiently. [15][16][17] Occasionally, the HNG serves as a self-powered monitor by utilizing the triboelectric, piezoelectric, and pyroelectric effects. [18][19][20] However, the simple stacking of the PPENG with the TENG seriously restricted application of HNG. On the other hand, electromagnetic radiation has become a serious pollution issue which threatens human health. [21,22] Epidemiological surveys have proved that excessive amounts of electromagnetic radiation can cause extensive biological damage effects especially for the pregnant women. [23][24][25] However, most conventional antielectromagnetic radiation equipments are cumbersome and cannot function well in the GHz range. A good solution for the problem is developing electronics which are wearable and portable to be antielectromagnetic. Above all, a new type wearable and portable HNG is much desired, which includes wide electromagnetic shielding range. DOIHere in this work, we developed a stretchable, portable, and wearable electromagnetic shielding HNG (ES-HNG) which composed...

Highly Stretchable Polymer Composite with Strain‐Enhanced Electromagnetic Interference Shielding Effectiveness

“…Recently, a variety of electrically conductive fillers including metallic nanowires and nanoparticles,2,5–7 liquid‐metal (LM) droplets,8–10 carbon‐based materials (e.g., graphene, carbon fibers, and carbon nanotubes)1,11,12 and 2D transition‐metal carbides13–15 have been incorporated into polymer matrix to yield EMI shielding polymer composites. While these composites are easily processable, lightweight, and mechanically flexible, their EMI shielding effectiveness (SE) is inevitably plagued by the reduction in electrical conductivity with the applied stretch,6–8,12,15,16 a common phenomenon in the current stretchable conductors 17–19.…”

Recent Advances in Triboelectric Nanogenerator‐Based Health Monitoring

“…Textile‐based TENGs possess merits such as good air permeability, flexibility and large‐scale production, therefore are desirable for wearable applications. Textile‐based TENGs have been applied to serve as self‐powered sensors for healthcare such as detection of respiration and sleep monitoring …”

“…The other type is that the TENG uses two whole pieces of textile as the substrates or triboelectric layers. Zhang et al reported a textile TENG‐based hybrid nanogenerator (HNG) that is able to monitor human abdominal respiration, with the function of protecting human health from electromagnetic radiation, as is shown in Figure . The TENG consists of a layer of conductive antielectromagnetic radiation fabric sandwiched between two layers of rubber.…”

“…f) Output currents in response to different respiratory amplitudes. Reproduced with permission . Copyright 2017, Wiley‐VCH.…”

An Amphiphobic Hydraulic Triboelectric Nanogenerator for a Self‐Cleaning and Self‐Charging Power System

“…Therefore, it cannot be directly used to drive most electronic devices which require a stable and continuous input power . The normal process is to transform the AC to direct current (DC) with a rectifier and then store the energy in an energy‐storage unit . Supercapacitor (SC) is an ideal candidate for green energy storage with high power density, excellent pulse charge–discharge character, superhigh cycling life, and safe operation .…”