Triboelectric Devices Research Articles

3D Bristle-Structured, Knitted-Fabric-Based Triboelectric Sensors for Machine Learning-Based Motion Recognition.

With the development of electronic technology, triboelectric-based sensors have been widely researched in fields such as healthcare, rehabilitation training, and sports assistance due to their manufacturing convenience and self-powering advantages. Among them, 3D fabric-based triboelectric sensors not only possess advantages such as easy mechanized production, good breathability, and ease of wearing but also their unique 3D structure enhances the specific surface area, thereby amplifying the sensitivity. This study proposes a 3D bristle-structured fabric made by a digital knitting technology that has not been studied widely for triboelectric devices. By applying the 3D bristle structure with a large specific surface area to the single jersey fabric, the effective contact area during friction can be increased, resulting in a higher surface charge density. Additionally, the microcapacitor-like effect provided by the numerous microstructures allows the device to store more surface charge, further improving the output performance. The study systematically investigates the output performance of four different structures assembled by single jersey and 3D bristle-structured fabrics. The optimal sample exhibits a 57% higher output voltage than that of the reference 2D fabric sample. The 3D bristle-structured fabric demonstrates linear high sensitivity and distinct output performance when used as a sensor. Finally, a machine learning integration is applied to judge motion to assist a baseball pitcher in a self-training system.

Functional silk-protein-based nanocomposites for light-stimulated and highly efficient triboelectric nanogenerators and charge storage devices

Overcoming the formidable challenge of achieving multifunctionality and a seamless bio-interface for triboelectric nanogenerators (TENGs) is a persistent pursuit. Here, a biomaterial-based nanocomposite designed for both energy harvesting and storage is presented. Molybdenum disulfide nanosheets (MoS2-NSs) are securely and uniformly incorporated into silk fibroin (SF). The resulting MoS2-NS/SF TENG, in conjunction with a tribo-negative polymer, exhibits an open-circuit voltage (Voc) of 0.95 kV, an average short-circuit current (Isc) of 2.2 μA, and an output power density of 60 μW/cm2—sufficient to illuminate 40 light-emitting diodes (LEDs). Notably, exposure to light triggers a substantial increase in Vocs by more than 26 %. Additionally, the MoS2-NS/SF nanocomposite enables efficient energy storage, with a frequency-dependent dielectric constant ranging from 28.2 to 2.6. This underscores its potential as a versatile electronic material platform for wearable devices, seamlessly integrating motion sensing, energy harvesting, and charge storage capabilities.

Rational Design of Triboelectric Materials and Devices for Self‐Powered Food Sensing

AbstractAgainst the backdrop of rapid advancements in 5G and Internet of Things (IoT) technologies, there is an urgent need to upgrade food sensing systems to achieve automation, digitalization, and intelligence. However, this transformation process faces numerous challenges. Triboelectric nanogenerators (TENGs), as an emerging energy conversion and sensing technology, play a crucial role in this context. They not only provide power to functional devices but also serve as sensors in multifunctional self‐powered food sensing systems, capable of detecting various physical and chemical information. This review explores the development of TENGs in the field of food sensing, focusing on the working principles of their self‐powered sensing. The review also systematically organizes and classifies the material and device designs used for TENGs in various food applications. Based on the performance of TENGs, a detailed introduction is provided on the specific applications of self‐powered food sterilization, self‐powered food quality monitoring, and self‐powered taste sensing in the field of food safety. Finally, this paper discusses the challenges and corresponding strategies of TENGs in the food sensing field. The aim is to further promote unmanned and smart services and management in the food sector and to provide new research perspectives.

Droplet-based triboelectric devices using liquid dielectrics for self-powered sensing applications

Triboelectric nanogenerators (TENGs) have attracted great interests by exploiting the complex interplay between contact electrification and electrostatic induction. The versatility of tribo-dielectric materials offers significant advantages for environmentally adaptive device design. In this regard, liquid dielectrics provide intimate contact between filled materials and high dielectric strength. Herein, a liquid dielectric-based TENGs system featuring a charge-transfer liquid layer is presented. A multifaceted summary is presented to illustrate the relationship between liquid dielectric materials and charge transfer mechanisms. New strategies for exploiting the dielectric properties of various liquids to control their electrical properties and monitor the parameters of liquid dielectric properties are highlighted. Additionally, it contributes to the advancement of self-powered sensing technology with increased flexibility, capacitance tuning, and sensor functionality through easy modularization. These achievements contribute to the understanding of charge transfer mechanisms in liquids and highlight their potential for self-powered sensing applications.

Modulating Contact Electrification With Metal‐Organic Frameworks in Flexible Triboelectric Nanogenerators for Kinetic Energy Harvesting and Self‐Powered Humidity Sensing Applications

AbstractHerein, we present a novel method for fabricating a triboelectric nanogenerator using Polyacrylonitrile (PAN) on both sides as triboelectric pairs, incorporating metal‐organic frameworks (MOFs) such as ZIF‐8, ZIF‐67, MIL‐100, and HKUST‐1 during the electrospinning process. The triboelectric properties of the MOF‐incorporated fibers are thus tailored and positioned within the triboelectric series for the first time. The resulting triboelectric polarity of the composite fiber is linked to the optical bandgap energy of the PAN and the MOF/PAN composite, facilitating electron transfer between materials of different work functions and leading to enhanced output in the developed triboelectric devices. Fascinatingly, the appropriate choice of MOF filler also displayed the potential for reversing the triboelectric polarity of PAN nanofiber. Consequently, incorporating ZIF‐8 and MIL‐100 into PAN nanofibers led notably to contrasting trends in triboelectric polarity, with the pair generating an open‐circuit output voltage of 100 V, short‐circuit current of 1.35 μA, and a power density of 18.4 mW/m2 respectively. The fabricated device demonstrated effectiveness for mechanical energy harvesting applications and also as a self‐powered humidity sensor, displaying rapid response to changes in ambient humidity levels with a maximum sensitivity of 2.14 V/%RH, for relative humidity range between 50 and 90% during the humidifying cycle.

Tailoring morphological and chemical contributions of nanoscale charge transfer for enhanced triboelectric nanogenerators.

Triboelectric devices, operating through contact electrification (CE) and electrostatic induction, have shown great promise in energy harvesting applications. However, optimizing charge transfer at the interface remains crucial for enhancing device performance. This study introduces a novel approach to harnessing CE by employing morphological and chemical modifications of polymers. Our strategy involves adjusting the elastomer base to curing agent ratio to fine-tune the chemical properties of polydimethylsiloxane (PDMS) and introducing morphological modifications through a peeling and flipping (P/F) process of PDMS off the Si-substrate. Unlike conventional methods, the P/F-method minimally alters the intrinsic properties of PDMS, creating nanoscale surface corrugations adiabatically. We explore the mechanical, tribological, and electrical properties of the surface at the nano-scale and demonstrate that our approach allows for precise control of energy dissipation and electric potential at the surface, thereby optimizing charge transfer. Furthermore, we show that using a plasma-treated Si-substrate can further increase device performance up to 80% without affecting other properties. This study presents a comprehensive strategy for fine-tuning CE to enhance the performance of triboelectric nanogenerators.

Tough and temperature-tolerance cellulose/polyacrylic acid/bentonite hydrogel with high ionic conductivity enables self-powered triboelectric wearable electronic devices

Solid-state zinc-ion hybrid supercapacitors (ZHSCs) featuring hydrogel electrolytes have become ideal for large-scale flexible energy storage. However, existing polyacrylic acid (PAA) hydrogel electrolytes often lack the combined traits of ionic conductivity, mechanical robustness, and temperature tolerance. Herein, a versatile PAA-based hydrogel electrolyte (ACBH-Zn) containing a ZnCl2-cellulose solution and bentonite (BT) is delivered, facilitated by cooperative coordination bonds and hydrogen bonds. The coordination bonds between Zn2+ and −COOH of PAA, in conjunction with cellulose and BT, alongside the abundant hydrogen bonds within cellulose and PAA, are conducive to upgrading mechanical strength and ionic conductivity, while the BT's lamellar structure further provides sufficient ion migration channels. Consequently, the ACBH-Zn showcases exceptional mechanical properties, satisfying ionic conductivity (88.9 mS cm−1), and excellent temperature tolerance at −60 °C (30.3 mS cm−1). The ACBH-ZHSC, when assembled, attains a remarkable maximum energy density (323.4 Wh kg−1), maintaining an impressive capacity retention rate (92 %) even after undergoing 10,000 cycles at 10.0 A g−1. Furthermore, the assembled self-powered triboelectric wearable electronic device effectively converts mechanical energy from human movement into electrical energy, enabling efficient storage and utilization, and offering promising insights into the application of flexible wearable devices.

Valorization of Food Waste: Utilizing Natural Porous Materials Derived from Pomelo-Peel Biomass to Develop Triboelectric Nanogenerators for Energy Harvesting and Self-Powered Sensing.

Food waste is an enormous challenge, with implications for the environment, society, and economy. Every year around the world, 1.3 billion tons of food are wasted or lost, and food waste-associated costs are around $2.6 trillion. Waste upcycling has been shown to mitigate these negative impacts. This study's optimized pomelo-peel biomass-derived porous material-based triboelectric nanogenerator (PP-TENG) had an open circuit voltage of 58 V and a peak power density of 254.8 mW/m2. As porous structures enable such triboelectric devices to respond sensitively to external mechanical stimuli, we tested our optimized PP-TENG's ability to serve as a self-powered sensor of biomechanical motions. As well as successfully harvesting sufficient mechanical energy to power light-emitting diodes and portable electronics, our PP-TENGs successfully monitored joint motions, neck movements, and gait patterns, suggesting their strong potential for use in healthcare monitoring and physical rehabilitation, among other applications. As such, the present work opens up various new possibilities for transforming a prolific type of food waste into value-added products and thus could enhance long-term sustainability while reducing such waste.

Application of triboelectric nanogenerator in self-powered motion detection devices: A review

Among today’s bustling lifestyles, the demand for autonomous, durable, and low-maintenance healthcare systems has surged, surpassing that of earlier periods. Nanostructured and environmentally friendly materials employed in nanogenerator technology offer a novel avenue for biomedical applications by harnessing biomechanical energy. Triboelectric Nanogenerators (TENGs) have emerged as comprehensive solutions, furnishing self-sustaining, eco-conscious, and compact devices. Recognizing the immense potential of TENGs, this paper presents a comprehensive overview of its motion detection. Our analysis delves into the versatility of TENG-based motion detection systems, providing wearable, user-friendly solutions powered by human motion. Recent advancements in triboelectric devices are cataloged, elucidating their structural intricacies, capabilities, performance metrics, and future prospects. In addition, the article also outlines the applications of different TENGs in motion monitoring, including contact, non-contact, and single-electrode mode. The evolution of intelligent wearable technologies has extended our capacities in communication, healthcare, and various other domains beyond our biological limits. Apart from the Internet of Things, the concept of Internet of bodies or beings is poised for rapid advancement, promising further transformation of our lifestyles. Conclusively, we present insights into forthcoming opportunities and plausible strategies to address anticipated hurdles.

Portable Multi-Layer Capsule-Shaped Triboelectric Generator for Human Motion Energy Harvesting.

This paper introduces a novel portable multi-layer capsule-shaped triboelectric generator (CP-TEG), aimed at optimizing the performance of triboelectric generator technology in terms of miniaturization, modularity, and efficient energy collection. The CP-TEG utilizes a unique multi-layer, stacked structure and an elliptical cylindrical design to increase the effective frictional area and enhance power generation efficiency. Its portable design allows for flexible application in various environments and scenarios. Experimental results demonstrate that the CP-TEG can maintain stable and efficient electrical output under various motion amplitudes and frequencies, and it shows good adaptability to the direction of motion excitation. With a motion amplitude of 7 cm and a frequency of 1.94 Hz, the CP-TEG can charge a 220 μF capacitor to 1.3 V within 100 s. The power generation unit's output voltage and current are more than three times higher than that of traditional single-layer contact-separation mode triboelectric devices. Particularly, its performance in harvesting energy from human motion underscores its effectiveness as a renewable energy solution for wearable devices. Through its innovative structural design and optimized working mechanism, the CP-TEG demonstrates excellent energy collection efficiency and application potential, offering new options for sustainable energy solutions and development.

A Triboelectric-Electromagnetic Hybrid Nanogenerator with Magnetic Coupling Assisted Waterproof Encapsulation for Long-Lasting Energy Harvesting.

Ocean energy harvesting based on a triboelectric nanogenerator (TENG) has great application potential, while the encapsulation of triboelectric devices in water poses a critical issue. Herein, a triboelectric-electromagnetic hybrid nanogenerator (TE-HNG) consisting of TENGs and electromagnetic generators (EMGs) is proposed to harvest water flow energy. A magnetic coupling transmission component is applied to replace traditional bearing structures, which can realize the fully enclosed packaging of the TENG devices and achieve long-lasting energy harvesting from water flow. Under the intense water impact, magnetic coupling reduces the possibility of internal gear damage due to excessive torque, indicating superior stability and robustness compared to conventional TENG. At the waterwheel rotates speed of 75rpm, the TE-HNG can generate an output peak power of 114.83mW, corresponding to a peak power density of 37.105Wm-3. After 5h of continuous operation, the electrical output attenuation of TENG is less than 3%, demonstrating excellent device durability. Moreover, a self-powered temperature sensing system and a self-powered cathodic protection system based on the TE-HNG are developed and illustrated. This work provides a prospective strategy for improving the output stability of TENGs, which benefits the practical applications of the TENGs in large-scale blue energy harvesting.

Advanced Triboelectric Applications of Biomass-Derived Materials: A Comprehensive Review.

The utilization of triboelectric materials has gained considerable attention in recent years, offering a sustainable approach to energy harvesting and sensing technologies. Biomass-derived materials, owing to their abundance, renewability, and biocompatibility, offer promising avenues for enhancing the performance and versatility of triboelectric devices. This paper explores the synthesis and characterization of biomass-derived materials, their integration into triboelectric nanogenerators (TENGs), and their applications in energy harvesting, self-powered sensors, and environmental monitoring. This review presents an overview of the emerging field of advanced triboelectric applications that utilize the unique properties of biomass-derived materials. Additionally, it addresses the challenges and opportunities in employing biomass-derived materials for triboelectric applications, emphasizing the potential for sustainable and eco-friendly energy solutions.

Unravelling the Ageing Effects of PDMS‐Based Triboelectric Nanogenerators

AbstractAgeing of elastomeric materials in triboelectric nanogenerators (TENGs) often leads to compromised electrical performance and can greatly affect their real‐world application as next‐generation energy harvesters and self‐powered sensors. Herein, the ageing behavior of PDMS‐based TENGs is investigated by probing the dielectric and mechanical properties of the membrane materials. Over time, ageing of PDMS after 17 months is evinced by a decline by 71%, 68% and 52% in open‐circuit voltage, short‐circuit current and charge transfer, respectively, and an increase by 6.8 times in surface charge decay rate. The reduced electrical performance can be attributed to a decrease in work function, dielectric constant, surface adhesion and heterogeneity in stiffness, as well as an increase in loss tangent. The effect of chemical chain scission on the PDMS surface is confirmed through nearfield infrared nanospectroscopy. This study gives insights into the underlying mechanism behind the ageing of PDMS‐based TENGs, paving the way to future work for ameliorating these ageing‐related issues with the aim to ensure long‐term stability of practical triboelectric devices.

A near-zero quiescent power breeze wake-up anemometer based on a rolling-bearing triboelectric nanogenerator

AbstractWind sensors have always played an irreplaceable role in environmental information monitoring and are expected to operate with lower power consumption to extend service lifetime. Here, we propose a breeze wake-up anemometer (B-WA) based on a rolling-bearing triboelectric nanogenerator (RB-TENG) with extremely low static power. The B-WA consists of two RB-TENGs, a self-waking-up module (SWM), a signal processing module (SPM), and a wireless transmission unit. The two RB-TENGs are employed for system activation and wind-speed sensing. Once the ambient wind-speed exceeds 2 m/s, the wake TENG (W-TENG) and the SWM can wake up the system within 0.96 s. At the same time, the SPM starts to calculate the signal frequency from the measured TENG (M-TENG) to monitor the wind speed with a sensitivity of 9.45 Hz/(m/s). After the wind stops, the SWM can switch off the B-WA within 0.52 s to decrease the system energy loss. In quiescent on-duty mode, the operating power of the B-WA is less than 30 nW, which can greatly extend the service lifetime of the B-WA. By integrating triboelectric devices and rolling bearings, this work has realized an ultralow quiescent power and self-waked-up wireless wind-speed monitoring system, which has foreseeable applications in remote weather monitoring, IoT nodes, and so on.

Ionic Liquid-Enhanced Assembly of Nanomaterials for Highly Stable Flexible Transparent Electrodes

HighlightsWe present a method that utilizes ionic liquid-enhanced nanomaterial assembly to fabricate highly stable and large-area MXene-silver nanowire electrodes with ordered layered structures.This approach emphasizes the use of hydrophobic and nonvolatile ionic liquids, which form stable interfaces with water by reducing interface energy, preventing the sedimentation loss of nanomaterials during assembly.The prepared electrodes not only exhibit excellent optoelectronic properties (9.4 Ω sq−1 sheet resistance and 93% transmittance), but also have exceptional antioxidant capacity.

A Tough Monolithic-Integrated Triboelectric Bioplastic Enabledby Dynamic Covalent Chemistry.

Electronic waste is a growing threat to the global environment and human health, raising particular concerns. Triboelectric devices synthesized from sustainable and degradable materials are a promising electronic alternative, but the mechanical mismatch at the interface between the polymer substrate and the electrodes remains unresolved in practical applications. This study uses the sulfhydryl silanization reaction and the chemical selectivity and site specificity of the thiol-disulfide exchange reaction in dynamic covalent chemistry to prepare a tough monolithic-integrated triboelectric bioplastic. The stress is dissipated by covalent bond adaptation to the interface interaction, which makes the polymer dielectric layer to the conductive layer have a good interface adhesion effect (220.55kPa). The interfacial interlocking of the polymer substrate with the conductive layer gives the triboelectric bioplastic excellent tensile strength (87.4MPa) and fracture toughness (33.3MJ m-3). Even when subjected to a tension force of 10000 times its weight, it still maintains a stable triboelectric output with no visible cracks. This study provides new insights into the design of reliable and environmentally friendly self-powered devices, which is significant for the development of flexible wearable electronics.

Biomimetic Exogenous "Tissue Batteries" as Artificial Power Sources for Implantable Bioelectronic Devices Manufacturing.

Implantable bioelectronic devices (IBDs) have gained attention for their capacity to conformably detect physiological and pathological signals and further provide internal therapy. However, traditional power sources integrated into these IBDs possess intricate limitations such as bulkiness, rigidity, and biotoxicity. Recently, artificial "tissue batteries" (ATBs) have diffusely developed as artificial power sources for IBDs manufacturing, enabling comprehensive biological-activity monitoring, diagnosis, and therapy. ATBs are on-demand and designed to accommodate the soft and confining curved placement space of organisms, minimizing interface discrepancies, and providing ample power for clinical applications. This review presents the near-term advancements in ATBs, with a focus on their miniaturization, flexibility, biodegradability, and power density. Furthermore, it delves into material-screening, structural-design, and energy density across three distinct categories of TBs, distinguished by power supply strategies. These types encompass innovative energy storage devices (chemical batteries and supercapacitors), power conversion devices that harness power from human-body (biofuel cells, thermoelectric nanogenerators, bio-potential devices, piezoelectric harvesters, and triboelectric devices), and energy transfer devices that receive and utilize external energy (radiofrequency-ultrasound energy harvesters, ultrasound-induced energy harvesters, and photovoltaic devices). Ultimately, future challenges and prospects emphasize ATBs with the indispensability of bio-safety, flexibility, and high-volume energy density as crucial components in long-term implantable bioelectronic devices.

Imine-Linked 2D Conjugated Porous Organic Polymer Films for Tunable Acid Vapor Sensing.

Two-dimensional (2D) films of conjugated porous organic polymers (C-POPs) can translate the rich in-plane functionalities of conjugated frameworks into diverse optical and electronic applications while addressing the processability issues of their crystalline analogs for adaptable device architectures. However, the lack of facile single-step synthetic routes to obtain large-area high-quality films of 2D-C-POPs has limited their application possibilities so far. Here, we report the synthesis of four mechanically robust imine-linked 2D-C-POP free-standing films using a single-step fast condensation route that is scalable and tunable. The rigid covalently bonded 2D structures of the C-POP films offer high stability for volatile gas sensing in harsh environments while simultaneously enhancing site accessibility for gas molecules due to mesoporosity by structural design. Structurally, all films were composed of exfoliable layers of 2D polymeric nanosheets (NSs) that displayed anisotropy from disordered stacking, evinced by out-of-plane birefringent properties. The tunable in-plane conjugation, different nitrogen centers, and porous structures allow the films to act as ultraresponsive colorimetric sensors for acid sensing via reversible imine bond protonation. All the films could detect hydrogen chloride (HCl) gas down to 0.05 ppm, far exceeding the Occupational Safety and Health Administration's permissible exposure limit of 5 ppm with fast response time and good recyclability. Computational insights elucidated the effect of conjugation and tertiary nitrogen in the structures on the sensitivity and response time of the films. Furthermore, we exploited the exfoliated large 2D NSs and anisotropic optoelectronic properties of the films to adapt them into micro-optical and triboelectric devices to demonstrate their real-time sensing capabilities.

Intermittent control switch characteristics of triboelectric electric hybrid energy harvesting devices and power management circuits

Renewable energy sources such as wind, vibration, and water wave energy are widely available in everyday life, where there are also scenarios where multiple renewable energy sources coexist. If multiple...

Research Progress in Fluid Energy Collection Based on Friction Nanogenerators.

In recent decades, the development of electronic technology has provided opportunities for the Internet of Things, biomedicine, and energy harvesting. One of the challenges of the Internet of Things in the electrification era is energy supply. Centralized energy supply has been tested over hundreds of years of history, and its advantages such as ideal output power and stable performance are obvious, but it cannot meet the specific needs of the Internet of Things, and distributed energy supply also has a large demand. Since the invention of nanogenerators, another promising solution for fluid energy harvesting has been opened up. The triboelectric nanogenerator is an emerging platform technology for electromechanical energy conversion, which can realize the collection of fluid energy such as wind energy and wave energy. In this paper, we first introduce the fundamentals of triboelectric nanogenerators and their applications in wind and wave energy harvesting devices. We then discuss the methods of device optimization in the next development of TENG and conclude by considering the future prospects and challenges for triboelectric nanogenerator harvesting devices.