3D Orthogonal Woven Triboelectric Nanogenerator for Effective Biomechanical Energy Harvesting and as Self‐Powered Active Motion Sensors

The development of wearable and large‐area energy‐harvesting textiles has received intensive attention due to their promising applications in next‐generation wearable functional electronics. However, the limited power outputs of conventional textiles have largely hindered their development. Here, in combination with the stainless steel/polyester fiber blended yarn, the polydimethylsiloxane‐coated energy‐harvesting yarn, and nonconductive binding yarn, a high‐power‐output textile triboelectric nanogenerator (TENG) with 3D orthogonal woven structure is developed for effective biomechanical energy harvesting and active motion signal tracking. Based on the advanced 3D structural design, the maximum peak power density of 3D textile can reach 263.36 mW m^?2 under the tapping frequency of 3 Hz, which is several times more than that of conventional 2D textile TENGs. Besides, its collected power is capable of lighting up a warning indicator, sustainably charging a commercial capacitor, and powering a smart watch. The 3D textile TENG can also be used as a self‐powered active motion sensor to constantly monitor the movement signals of human body. Furthermore, a smart dancing blanket is designed to simultaneously convert biomechanical energy and perceive body movement. This work provides a new direction for multifunctional self‐powered textiles with potential applications in wearable electronics, home security, and personalized healthcare.     

非接触式摩擦纳米发电机的最新研究进展

目的 随着科学技术的快速发展,人们对可持续能源的需求不断增加。摩擦纳米发电机(TENG)利用各类微弱机械能实现自供电,有利于缓解这一需求。非接触式摩擦纳米发电机(NC?TENG)可以提高稳定性和使用寿命。总结NC?TENG的最新研究进展,为NC?TENG的结构设计、性能优化提供有益参考。方法 根据NC?TENG的器件结构与输出性能优化方法,介绍不同NC?TENG及其性能,重点综述其在智能包装领域的应用,并对未来的性能优化和应用工作进行展望。结果 基于不同的组装结构,通过介电常数调制、添加电荷捕获中间层等性能优化方案可以有效地避免静电放电问题,提高NC?TENG的电荷保留率。结论 NC?TENG相较于TENG,有着更高的稳定性和更长的使用寿命,在应对能源危机和推动新兴电子产品方面显示出巨大的潜力,预计在智能包装领域有着广泛的应用前景。     

Thermal-Driven Soft-Contact Triboelectric Nanogenerator for Energy Harvesting and Industrial Cooling Water Monitoring

In this paper, a quaternary dielectric soft-contact rotary triboelectric nanogenerator (QDSR-TENG) of low frictional resistance is fabricated for combining TENG with a shape memory alloy (SMA) engine. The introduction of rabbit fur brush and FEP brush results in charge pumps with a partially soft contact structure. Benefiting from the low friction loss of the structure, the QDSR-TENG can operate stably and continually for 100k cycles without significant output degradation. The SMA engine exhibits thermally induced phase transformation and super-elasticity and can be utilized for harnessing waste heat energy. The thermal-driven QDSR-TENG can operate with a water source of 43 °C with a distinguishable response to the variation of temperatures. Such a low starting temperature not only promotes the harvesting of low-grade thermal energy, but also results in a self-monitoring industrial cooling water system. The coupled elastocaloric power and cooling cycle proposed in the thermal-driven QDSR-TENG opens a new paradigm for the application in energy harvesting and smart sensing.     

基于石墨烯森林电极的摩擦纳米发电机

本研究提出并制备了一种以石墨烯森林为电极的摩擦纳米发电机。利用等离子体增强化学气相沉积工艺制备了与其它墙形竖直薄片状的石墨烯形貌差异较大的石墨烯森林。此石墨烯森林具有低薄膜电阻((110±5) Ω/□)以及独特的离散“树状”结构, 有利于石墨烯森林与其他电极材料之间的接触和摩擦。根据石墨烯森林的形貌优势, 将聚酰亚胺膜和石墨烯森林膜作为电极组装摩擦纳米发电机, 其开路电压可达20 V, 短路电流可达0.75 μA。此外, 还讨论了基于石墨烯森林的摩擦纳米发电机的工作原理。最后, 利用此纳米发电机点亮了演示电路中三个不同颜色的LED, 证明了石墨烯森林在摩擦纳米发电机中的有效应用。     

Enhanced Mechanical Energy Harvesting in Triboelectric Nanogenerator by the Reinforcement of Polypyrrole-Decorated rGO Sheets in PDMS

Energy harvesting triboelectric nanogenerators (TENGs) to scavenge unused mechanical energy have received significant attention in this decade. Herein, the development of reduced graphene oxide (rGO):polypyrrole (PPy) hybrid-modified polydimethylsiloxane (PDMS) as TENG for various device applications is reported. The bulk of PDMS is altered by different fillers such as rGO, PPy, and the binary hybrids of rGO and PPy with varying weight ratios. Among various PDMS composites, 1 wt% of 1:8 rGO:PPy–PDMS composite exhibits higher TENG responses than other PDMS composite. The superior TENG performances of 1 wt% 1:8 rGO:PPy–PDMS composite are attributed to the formation of intensified negative charges inside the PDMS matrix. This charge intensification in the composite is due to various mechanisms, including the charge trapping ability of rGO:PPy filler, microcapacitor formation by introducing hybrid filler in the system with proper conducting networks, and the electron-donating nature of PPy conducting polymer. A 3D stacked device proposed using 1 wt% 1:8 rGO:PPy–PDMS composite delivered a short-circuit current of 16 μA and an open-circuit potential of 60 V by simple palm pressing. Also, the ability of the stacked device for charging/powering portable devices and light-emitting diodes is demonstrated.     

纸/纤维素基摩擦纳米发电机的研究进展

能源危机与环境污染是全世界可持续发展面临的主要挑战之一.摩擦纳米发电机是一种高效的能源装置,具有可持续、 较高的电输出性能和材料选择不受限制等突出特性,其独特的自驱动系统可以确保设备的持续可靠供电.纤维素及其衍生物来源广泛、 环境友好,是一种可再生、 易降解的天然大分子材料,基于天然纤维素制备的电极材料设计制作的纸/纤...     

Triboelectric energy harvesting with surface-charge-fixed polymer based on ionic liquid

A novel triboelectric energy harvester has been developed using an ionic liquid polymer with cations fixed at the surface. In this report, the fabrication of the device and the characterization of its energy harvesting performance are detailed. An electrical double layer was induced in the ionic liquid polymer precursor to attract the cations to the surface where they are immobilized using a UV-based crosslinking reaction. The finalized polymer is capable of generating an electrical current when contacted by a metal electrode. Using this property, energy harvesting experiments were conducted by cyclically contacting a gold-surface electrode with the charge fixed surface of the polymer. Control experiments verified the effect of immobilizing the cations at the surface. By synthesizing a polymer with the optimal composition ratio of ionic liquid to macromonomer, an output of 77 nW/cm² was obtained with a load resistance of 1 MΩ at 1 Hz. This tuneable power supply with a μA level current output may contribute to Internet of Things networks requiring numerous sensor nodes at remote places in the environment.     

High-Output Single-Electrode Droplet Triboelectric Nanogenerator Based on Asymmetrical Distribution Electrostatic Induction Enhancement

Droplet-based triboelectric nanogenerators (D-TENGs) have recently gained much attention due to their great potential in harvesting energy. However, the output performance of conventional single-electrode droplet-based TENGs is limited owing to low induced electrification efficiency. The asymmetric distribution of electric fields on both sides of the electrode edge enhances the electrostatic induction process and improves the output performance of D-TENG. Herein, an induced electrification-enhanced droplet-based triboelectric nanogenerator (IED-TENG) is developed to effectively enhance the output performance by simultaneously optimizing the electrode structure and the dynamics of the water droplet. One droplet falling from a height of 30 cm results in a −70 V output voltage and −6 µA short-circuit current, which is 70 times and 20 times the full-inductive-electrode mode, respectively. The working principle and the relationship between electric signal and droplet dynamics are analyzed in detail. Moreover, the peak output voltage can reach −110 V, and the peak current can get −140 µA by using the power generation of multiple water droplets. The present protocol provides an easy and reproducibility strategy in energy harvesting and sensing areas.     

A New Facile Route to Flexible and Semi‐Transparent Electrodes Based on Water Exfoliated Graphene and their Single‐Electrode Triboelectric Nanogenerator

Wearable technologies are driving current research efforts to self‐powered electronics, for which novel high‐performance materials such as graphene and low‐cost fabrication processes are highly sought.The integration of high‐quality graphene films obtained from scalable water processing approaches in emerging applications for flexible and wearable electronics is demonstrated. A novel method for the assembly of shear exfoliated graphene in water, comprising a direct transfer process assisted by evaporation of isopropyl alcohol is developed. It is shown that graphene films can be easily transferred to any target substrate such as paper, flexible polymeric sheets and fibers, glass, and Si substrates. By combining graphene as the electrode and poly(dimethylsiloxane) as the active layer, a flexible and semi‐transparent triboelectric nanogenerator (TENG) is demonstrated for harvesting energy. The results constitute a new step toward the realization of energy harvesting devices that could be integrated with a wide range of wearable and flexible technologies, and opens new possibilities for the use of TENGs in many applications such as electronic skin and wearable electronics.     

Single‐Step Fluorocarbon Plasma Treatment‐Induced Wrinkle Structure for High‐Performance Triboelectric Nanogenerator

A triboelectric nanogenerator (TENG) has been thought to be a promising method to harvest energy from environment. To date, the utilization of surface structure and material modification has been considered the most effective way to increase its performance. In this work, a wrinkle structure based high‐performance TENG is presented. Using the fluorocarbon plasma treatment method, material modification and surface structure are introduced in one step. The output ability of TENG is dramatically enhanced. After the optimization of plasma treatment, the maximum current and surface charge density are 182 μA about 165 μC m^?2. Compared with untreated TENG, the wrinkle structure makes the current and surface charge density increase by 810% and 528%, separately. X‐ray photoelectron spectroscopy is employed to analyze the chemical modification mechanism of this fluorocarbon plasma treatment. Facilitated by its high output performance, this device could directly light 76 blue light emitting diodes under finger typing. The output electric energy could be stored then utilized to power a commercial calculator. As a result of the simple fabrication process and high output ability, devices fabricated using this method could bring forward practical applications using TENGs as power sources.     

A Hybrid Biofuel and Triboelectric Nanogenerator for Bioenergy Harvesting

Various types of energy exist everywhere around us,and these energies can be harvested from multiple sources to power micro-/nanoelectronic system and even personal electronic products.In this work,we proposed a hybrid energy-harvesting system(HEHS)for potential in vivo applications.The HEHS consisted of a triboelectric nanogenerator and a glucose fuel cell for simultaneously harvesting biomechanical energy and biochemical energy in simulated body fluid.These two energy-harvesting units can work individually as a single power source or work simultaneously as an integrated system.This design strengthened the flexibility of harvesting multiple energies and enhanced corresponding electric output.Compared with any individual device,the integrated HEHS outputs a superimposed current and has a faster charging rate.Using the harvested energy,HEHS can power a calculator or a green light-emitting diode pattern.Considering the widely existed biomechanical energy and glucose molecules in the body,the developed HEHS can be a promising candidate for building in vivo self-powered healthcare monitoring system.     

Theoretical Comparison,Equivalent Transformation,and Conjunction Operations of Electromagnetic Induction Generator and Triboelectric Nanogenerator for Harvesting Mechanical Energy

Triboelectric nanogenerator (TENG) is a newly invented technology that is effective using conventional organic materials with functionalized surfaces for converting mechanical energy into electricity, which is light weight, cost‐effective and easy scalable. Here, we present the first systematic analysis and comparison of EMIG and TENG from their working mechanisms, governing equations and output characteristics, aiming at establishing complementary applications of the two technologies for harvesting various mechanical energies. The equivalent transformation and conjunction operations of the two power sources for the external circuit are also explored, which provide appropriate evidences that the TENG can be considered as a current source with a large internal resistance, while the EMIG is equivalent to a voltage source with a small internal resistance. The theoretical comparison and experimental validations presented in this paper establish the basis of using the TENG as a new energy technology that could be parallel or possibly equivalently important as the EMIG for general power application at large‐scale. It opens a field of organic nanogenerator for chemists and materials scientists who can be first time using conventional organic materials for converting mechanical energy into electricity at a high efficiency.