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This paper systematically investigates the effective parameter on the performance of polydimethylsiloxane/graphene (PDMS@Gr)-based triboelectric nanogenerators (TENGs) as well as their applications. PDMS@Gr films containing 0, 0.05, 0.5, 1, and 1.5 wt.% graphene are synthesized, and their surface characteristics, mechanical behavior, and electrical properties are characterized. Vertical contact-separation mode TENGs are fabricated, and their performance is evaluated. The results demonstrate that the surface roughness and surface charge density are the most critical parameters for the performance of PDMS@Gr-based TENGs compared to the electrical and mechanical properties of the friction layers. The PDMS@Gr-based TENG with 1 wt.% graphene shows the highest power output of 2.6 W/m2 at an optimized working condition (5 Hz and 15 N). It also exhibits stable power output until 15,000 working cycles and displays battery-free applications by powering a light-emitting diode (LED) array, a calculator, a digital watch, and a digital thermometer.

Highlights A bionic phase-locked structure-inspired iontronic triboelectric gel is proposed with good mechanical compliance for wearable haptic sensing applications. Competitive hydrogen bonding systems are constructed through polymer-solvent-nonsolvent interactions, and regeneration of polymers with weak hydrogen bond donors triggers controlled phase separation. Self-powered haptic skin constructed with iontronic triboelectric gel has a modulus (150.6 kPa) and stretchability (> 400%) similar to that of the human body, enabling fidelity transmission of haptic signals and precise recognition of sensing objects.

Abstract We investigated the polarity dependence of a capacitive energy management circuit in a triboelectric nanogenerator (TENG) power system. In a half-wave rectifying circuit, the Simulation Program with Integrated Circuit Emphasis and analytical models show that the charge dump to the load varied depending on the polarity of the rectifying circuit even with the same charge output from TENG. Depending on the polarity of the rectifying circuit, a fast saturation of the direct current (DC) output voltage or a high DC output voltage was obtained. Experiments with a half-wave rectifier and Bennet doubler confirmed our simulation and theoretical results. The charge dump from the minimum capacitance of the separated TENG to the load capacitance and the charge dump from the maximum capacitance of the contacted TENG to the load resulted in asymmetric charging behavior. We concluded that it is necessary to analyze the TENG and the capacitive energy management circuit as a single system rather than considering them as independent units in the rectifying circuit of the TENG. This work can provide insights for the design of triboelectric energy harvesting systems.

As a sustainable energy source, sound is abundant in the environment, but its effective conversion into electrical energy remains a technical challenge. Triboelectric nanogenerators (TENGs) have made significant progress in addressing this issue, enabling the efficient capture of low-frequency sound waves and their transformation into usable power. This review explores the core principles behind acoustic energy harvesting using TENGs and examines key advancements in materials and resonator designs, including Helmholtz and quarter-wavelength configurations, which enhance energy conversion. Recent breakthroughs in TENG technologies are also highlighted, focusing on specialized mechanisms and innovative structural designs that improve sound wave collection and energy transfer. The review also looks into the various applications of TENGs, including harnessing urban noise, enhancing voice recognition systems, and powering wearable devices. Finally, challenges and future directions for expanding the use of acoustic energy harvesting technologies are discussed,focusing on their potential to provide practical and scalable energy solutions for various applications.

The emergence of digital twins has ushered in a new era in civil engineering with a focus on achieving sustainable energy supply, real‐time sensing, and rapid warning systems. These key development goals mean the arrival of Civil Engineering 4.0.The advent of triboelectric nanogenerators (TENGs) demonstrates the feasibility of energy harvesting and self‐powered sensing. This review aims to provide a comprehensive analysis of the fundamental elements comprising civil infrastructure, encompassing various structures such as buildings, pavements, rail tracks, bridges, tunnels, and ports. First, an elaboration is provided on smart engineering structures with digital twins. Following that, the paper examines the impact of using TENG‐enabled strategies on smart civil infrastructure through the integration of materials and structures. The various infrastructures provided by TENGs have been analyzed to identify the key research interest. These areas encompass a wide range of civil infrastructure characteristics, including safety, efficiency, energy conservation, and other related themes. The challenges and future perspectives of TENG‐enabled smart civil infrastructure are briefly discussed in the final section. In conclusion, it is conceivable that in the near future, there will be a proliferation of smart civil infrastructure accompanied by sustainable and comprehensive smart services. [ABSTRACT FROM AUTHOR]

In this study, a novel and sustainable triboelectric material is successfully designed and developed by extracting keratin from recycled fur and combining it with chitosan to create a keratin/chitosan triboelectric nanogenerator (CK‐TENG) device. The device is designed for the simultaneous treatment of waste and the generation of green and clean energy, crucial for addressing global challenges. CK is prepared through a freeze‐drying method to overcome the weak mechanical properties of keratin and achieve a high surface contact area, which is important for triboelectric properties. The results showed that the output voltage is improved by 375% compared to the TENG without keratin, with values reaching 322 V under a 6 N. It produced a high power density of 14.4 W m−2 and excellent cyclic stability for more than 8000 cycles, which are crucial for practical applications. Further, the potential applications are also studied, and the results showed that it can turn on over 250 light‐emitting diodes (LEDs), display liquid crystal display (LCD), and charge capacitors under 6 N. Moreover, it is successful in harvesting energy from waste vibrations, acoustic energy, and as a shoe, and the electrical output is utilized to power electronic devices. Furthermore, the power density harvested by the device is higher than that of TENG devices made with keratin‐rich materials. Therefore, this study paves the way for the use of keratin‐based bio‐waste materials for clean and green energy production, which can play significant roles in applications such as the charging of electronic devices, biomedicine, sensors, and smart textiles. [ABSTRACT FROM AUTHOR]

Mass transfer technology for large quantities of tiny substances, such as electronic chips and drug particles, plays a crucial role in many industries. This study proposes a transferring system for large quantities of small objects based on the synergism of triboelectric nanogenerators (TENGs) and photo‐responsive dielectric materials. TENG device can provide an output voltage of over 8 kV within a rotation time of 40 ms and the titanium oxide phthalocyanine (TiOPc) photoconductive films are fabricated as the photo‐responsive interface, in order to match the output impedance of TENG. The transfer system enables a maximum adsorption load of 98 mg mm−2, which is enough for handling all common electronics chips/wafers. Under the stimulation of laser light, the conductivity of the TiOPc interface can be increased by two orders of magnitude within 1 ms, which leads to the vanish of the surface potential on the laser spot and the release of patterned or pointed object. This photo‐responsive strategy can achieve both large quantity transfer of tiny objects and highly selective release of the element at designed position. This collaborative mechanism of electrostatic force and photoconductivity provides a different approach for realizing efficient and precise Mass transfer system of semiconductor and chip industry. [ABSTRACT FROM AUTHOR]

Nowadays, magnetic materials are also drawing considerable attention in the development of innovative energy converters such as triboelectric nanogenerators (TENGs), where the introduction of magnetic materials at the triboelectric interface not only significantly enhances the energy harvesting efficiency but also promotes TENG entry into the era of intelligence and multifunction. In this review, we begin from the basic operating principle of TENGs and then summarize the recent progress in applications of magnetic materials in the design of TENG magnetic materials by categorizing them into soft ferrites and amorphous and nanocrystalline alloys. While highlighting key role of magnetic materials in and future opportunities for improving their performance in energy conversion, we also discuss the most promising choices available today and describe emerging approaches to create even better magnetic TENGs and TENG-based sensors as far as intelligence and multifunctionality are concerned. In addition, the paper also discusses the integration of magnetic TENGs as a power source for third-party sensors and briefly explains the self-powered applications in a wide range of related fields. Finally, the paper discusses the challenges and prospects of magnetic TENGs. [ABSTRACT FROM AUTHOR]

In advancing the transition of the energy sector toward heightened sustainability and environmental friendliness, biopolymers have emerged as key elements in the construction of triboelectric nanogenerators (TENGs) due to their renewable sources and excellent biodegradability. The development of these TENG devices is of significant importance to the next generation of renewable and sustainable energy technologies based on carbon-neutral materials. This paper introduces the working principles, material sources, and wide-ranging applications of biopolymer-based triboelectric nanogenerators (BP-TENGs). It focuses on the various categories of biopolymers, ranging from natural sources to microbial and chemical synthesis, showcasing their significant potential in enhancing TENG performance and expanding their application scope, while emphasizing their notable advantages in biocompatibility and environmental sustainability. To gain deeper insights into future trends, we discuss the practical applications of BP-TENG in different fields, categorizing them into energy harvesting, healthcare, and environmental monitoring. Finally, the paper reveals the shortcomings, challenges, and possible solutions of BP-TENG, aiming to promote the advancement and application of biopolymer-based TENG technology. We hope this review will inspire the further development of BP-TENG towards more efficient energy conversion and broader applications. [ABSTRACT FROM AUTHOR]

Three congenetic Cd-MOFs with different pores were successfully synthesized via solvent-regulated strategy, and they were used as friction materials to regulate the TENG output, which could drive electrolysis systems to promote the direct bromination of aromatic compounds in high yields with good regioselectivity. [Display omitted] Optimizing friction materials based on molecular diversity in a molecular framework system is an effective method to improve the output performance of triboelectric nanogenerators (TENGs). In this study, three cadmium(II) metal–organic frameworks (Cd-MOFs) with different cavities were synthesized solvothermally by the assembly of cadmium nitrate (Cd(NO 3) 2 ·4H 2 O), 4′,4′''-carbonylbis(([1,1′-biphenyl]-3,5-dicarboxylic acid)) (H 4 CBBD), and trans -1,2-bis(4-pyridyl)ethylene (4,4′-bpe) via a solvent-regulated strategy. The topology and porosity of Cd-MOFs could be controlled effectively by the solvent constituents and were demonstrated to be closely related to their triboelectric behaviors. Theoretical calculations and experimental characterizations revealed that the TENGs fabricated by the Cd-MOF with maximum porosity exhibited the best triboelectric performance owing to the enhanced specific surface area and surface potential. In the applications, the high-output TENGs can be successfully used as an efficient power supply for electrochemical systems, enabling the direct bromination of aromatic compounds in high yields with good regioselectivity. This study provides a simple and feasible method to optimize positive friction materials at the molecular level and develops the practical applications of TENGs in electrochemical systems. [ABSTRACT FROM AUTHOR]

Disc and cylinder‐based triboelectric nanogenerators (TENGs) have great potential for harvesting wind energy. However, a significant challenge faced by these TENGs is the wear issues arising from the required close contact between tribo‐materials, especially at high frequencies. In response to this challenge, a gear‐slider TENG (GS‐TENG) is designed to transition from continuous close‐contact friction mode to intermittent contact. Working in unison with the central gear and two sliders, four units housed within GS‐TENG yield electrical output through periodic contact and separation. During a durability test of 845 000 cycles, the short‐circuit current only experiences a slight decrease, going from 25.38 to 24.03 µA, retaining 94.68% of its initial value. Operating at a matched impedance of 6 MΩ, GS‐TENG at M1 achieves a peak power density of 386 mW m−2, exceeding some previously proposed solutions in wind harvesting. When integrated into a wind speed sensing system, the GS‐TENG has a wide sensing range (13.1 to 28 m s−1) with a maximum error of 3.39%. This work demonstrates a rotation‐to‐translation strategy that lays the foundation for long‐term, high‐frequency wind energy harvesting and the development of a self‐powered wind sensing system. [ABSTRACT FROM AUTHOR]

Accurate measurement of complicated multiphase flow is crucial to the safety and efficiency of petroleum and chemical industrial facilities. However, the existing multiphase flow detection techniques are not applicable to pipelines in remote regions including deserts or deep seas, due to the high cost of providing a stable power supply. Herein, a self‐powered multiphase flow sensor, composed of a liquid‐driven triboelectric nanogenerator (TENG) ‐based signal generator, a ring‐type transmitter, and a string‐type receiver, is proposed. Theoretical modeling of displacement current between transmitter and receiver implies that the received current signal can accurately reflect the wetting state of the receiver, validated by a combined experimental (accuracy above 97%) and simulation study. Coupling with a quantitative analysis algorithm, a multiphase flow detection system with numerous receiver measurement points is developed to precisely monitor various flow parameters, including slug frequency (one point), slug length (two points), and flow pattern (four points), which is verified by spontaneous high‐speed camera recordings of water–air flow. The present work provides a paradigm‐shift way to develop a self‐powered, inexpensive, and accurate technique to detect multiphase flow at remote industrial facilities. [ABSTRACT FROM AUTHOR]

The dissipation of charges by aging or under the effect of humid conditions considerably impedes a broader utilization of electrostatic fields in aerosol filtration. This study introduces a respiration‐driven air filter (RAF) that continuously generates triboelectric charges within a pair of tribolayers, which facilitates a sustained filtration performance. Such system is integrated in a multilayer unit that is inserted in personal protective equipment (RAFM) to efficiently capture, sense, and degrade airborne pollutants with no need for external power sources. The triboelectric nanogenerator‐based RAF continuously replenishes static charges and maintains an electrostatic field through breathing by the effect of contact‐electrification between two cellulose‐based tribolayers: a cellulose/metal organic framework cryogel (electron donor) and a cellulose–based electrospun membrane (electron acceptor). Notably, the triboelectric field of the RAF's tribolayer pair substantially enhances both the filtration efficiency (up to 93.8% for 0.3 µm particulate matter) and sensing/catalytic degradation (ammonia; degradation >20%). When integrated in a circuit module, the RAFM effectively monitors respiration dynamics, acting as a breathing indicator/regulator. Overall, this study adds to the promise of tribogeneration through cellulose‐based materials and its application in exposure‐risk operations. [ABSTRACT FROM AUTHOR]

Graphene has attracted considerable interest for next‐generation electronics. However, the absence of natural bandgap has limited the current on/off ratio of graphene‐based transistors. Vertical integration of 2D heterostructures offers a promising approach to address this challenge, enabling high‐current‐density vertical field‐effect transistor (VFET) with large on/off ratio. Here, a triboelectric potential‐powered VFET with a vertical stacked graphene/MoS2 heterostructure and a sliding‐mode triboelectric nanogenerator (TENG) coupled with gate dielectrics are proposed. The tribotronic VFET has an ultrashort channel length in vertical direction, exhibiting excellent current driving capability with an ultrahigh on‐state current density of 950 A cm−2 and a good current on/off ratio of 630. It also demonstrates reconfigurable diode behavior with a rectification ratio over 102. Temperature‐dependent studies are applied to tribotronic devices for the first time, indicating an effective modulation on the Schottky barrier height of 150 meV by the triboelectric potential. A green LED pixel is driven by the tribotronic VFET as a demonstration to work as a tactile interactive light‐emitting device. The demonstrated tribotronic vertical device offers a promising strategy for integrating various 2D layered materials with TENG in vertical direction, enabling 3D integration of low‐power and interactive devices for next‐generation electronics. [ABSTRACT FROM AUTHOR]

[Display omitted] Contact electrification (CE) is a well-known phenomenon that ubiquitously exists in the charge transfer between solid–solid (S-S) or solid–liquid (S-L) and plays pivotal roles in energy harvesting and self-powered sensing. However, little is known about the CE mechanism during the phase transition. Here, we investigated the mechanism of charge transfer between a representative crystalline ice and a dielectric material during the solid-to-liquid phase transition. This study aimed to determine how the phase transition affects the charge transfer efficiency. Before ice starts melting, electron transfer within S-S contact predominated. As the melted micro-droplets smoothed the rough surface of the ice, the contact area between the materials increased, resulting in a roughly 6-fold enhancement of charge transfer. When the ice melted, droplets condensed on the surface and established S-L contact with the dielectric material. It resulted in the formation of an electrical double layer (EDL) composed of ions and electrons at the contact interface, effectively shielding the surface net charge of the dielectric material and impeding charge transfer between the materials. After the complete melting of ice into water, a stable S-L contact was established, and the EDL formed a stable and strong screening effect, resulting in the lowest level of charge transfer. The findings contributed to enhancing knowledge about interaction and charge transfer between different substances in dynamic phase transition scenarios. It could also provide valuable insights into the optimization and advancement of CE-based triboelectric nanogenerators for energy harvesting and self-powered sensing. [ABSTRACT FROM AUTHOR]

In recent years, renewable and sustainable triboelectric nanogenerators have attracted attention due to their high energy conversion rate, and enhancing their functionality further contributes to their applicability across various fields. A pH-sensitive triboelectric nanogenerator (pH-TENG) has been prepared by electrostatic spinning technology, with anthocyanin as the pH indicator and environmentally friendly polyvinyl alcohol (PVA) as the substrate. Among many friction-negative materials, the pH-TENG exhibits the best combination with fluorinated ethylene propylene (FEP) and yields an open-circuit voltage of 62 V, a short-circuit current of 370 nA, and a transferred charge of 21.8 nC. At a frequency of 3 Hz, it can charge a 4.7 μF capacitor to 2 V within 45 s, effectively powering a thermometer. Furthermore, the presence of anthocyanin does not affect the pH-TENG's power generation performance and enables the monitoring of a wide range of environmental pH changes, with an ΔE change of 28.8 ± 7.6. Therefore, pH-TENG prepared with environmentally friendly materials can bring new available materials to the biological and medical fields. [ABSTRACT FROM AUTHOR]

Distributed micro‐energy harvesting devices offer the flexibility, sustainability, and multi‐scenario applicability that will be critical to wearable electronic products in the Internet of Things. The radiofrequency and triboelectric (RF‐TE) hybrid energy harvester (HEH) concept and prototype is presented for the first time, to simultaneously capture the energy from ambient electromagnetic waves and biological motions. The proposed hybrid energy harvesting system consists of a wearable rectenna, a triboelectric nanogenerator (TENG), and a power management circuit (PMC). Among them, the all‐fabric rectenna exhibits good impedance matching characteristics in the ISM frequency. The flexible TENG unit can generate a maximum power density of 0.024 µW cm−2. The designed multifunctional fabric‐based PMC can considerably enhance the controllability of harvested hybrid energy. Additionally, a normalizable fabric circuit board quasi surface mount technology (FCB‐SMT) is proposed to integrate all modules on the same fabric substrate in one step, making the entire system superior mechanical robustness. The proposed wearable fabric‐based RF‐TE hybrid energy harvester is capable of successfully driving consumer electronics (such as sensors, watches, etc.). It provides a new energy solution strategy for self‐powered wearable electronic devices and is anticipated to encourage the efficient utilization of renewable energy. [ABSTRACT FROM AUTHOR]

The precision in controlling fluid flow is crucial for the efficiency of microchannel devices. Consequently, it is essential to monitor the fluid within microchannels in real time. However, the microchannel flow's susceptibility to disturbance and small size present challenges in sensing. A Liquid‐Solid Triboelectric Nanogenerator (TENG) with grating electrodes is proposed for non‐invasive sensing of liquid plug movements in microchannels and is suitable for use with opaque channels. This sensor operates on the principle of initiating multiple pulse signals via grating electrodes. And analyze the motion of the liquid plug by the time difference between the signal peaks. It facilitates the measurement of liquid plug count, average speed, average acceleration, and the detection of flow direction. The liquid plug counters, and flow direction sensors yielded clear and distinguishable signals. The liquid plug average speed sensor achieves a 95% accuracy rate, and the acceleration sensor accurately distinguishes speed trends of the liquid plug with more than 85% precision. Grating electrodes are effectively employed for motion sensing. Analyzing the motion of an object by the time difference between voltage peaks offers greater stability than voltage magnitude analysis. Four portable prototypes are designed to make them applicable for fluid sensing in microchannel devices. [ABSTRACT FROM AUTHOR]

Screen sensors are the most commonly used human-machine interfaces in our everyday life, which have been extensively applied in personal electronics like cellphones. Touchless screen sensors are attracting growing interest due to their distinct advantages of high interaction freedom, comfortability, and hand hygiene. However, the material compositions of current touchless screen sensors are rigid and fragile, hardly meeting the needs of wearable and stretchable on-skin electronics development. Additionally, these touchless screen sensors are also restricted by high power consumption, limited gesture types of recognition, and the requirement of light conditions. Here, we report a stretchable on-skin touchless screen sensor (OTSS) enabled by an ionic hydrogel-based triboelectric nanogenerator (TENG). Compared with current touchless screen sensors, the OTSS is stretchable, self-powered, and competent to recognize diverse gestures by making use of charges naturally carried on fingers without the need of sufficient light conditions. An on-skin noncontact screen operating system is further demonstrated on the basis of the OTSS, which could unlock a cellphone interface in touchless operation mode on the human skin. This work for the first time introduces the on-skin touchless concept to screen sensors and offers a direction to develop new-generation screen sensors for future cellphones and personal electronics. [ABSTRACT FROM AUTHOR]

Human–machine interactions (HMIs) have advanced rapidly in recent decades in the fields of healthcare, work, and life. However, people with disabilities and other mobility problems do not have corresponding high-tech aids for them to enjoy the convenience of HMIs. In this paper, we propose a sensor with a wave-shaped (corrugated) electrode embedded in a friction layer, which exhibits high sensitivity to skin fold excitation and enormous potential in HMIs. Attributing to the wave-shaped electrode design, it has no built-in cavities, and its small size allows it to flexibly cope with folds at different angles. By specifying the carbon nanotube hybrid silicone film as the electrode layer material and silicone film as the friction layer, good electrical output performance, tensile properties, and biocompatibility can be achieved. Then, the sensor is tested on various joints and skin folds of the human body, the output signals of which can be distinguished between normal physiological behavior and test behavior. Based on this sensor, we designed a medical alarm system, a robotic arm assistive system, and a cell phone application control system for the disabled to help them in the fields of healthcare, work, and life. In conclusion, our research presents a feasible technology to enhance HMIs and makes a valuable contribution to the development of high-tech aids for the disabled. [ABSTRACT FROM AUTHOR]

An enormous number of wireless sensing nodes (WSNs) are of great significance for the Internet of Things (IoT). It is tremendously prospective to realize the in-situ power supply of WSNs by harvesting unutilized mechanical vibration energy. A harmonic silicone rubber triboelectric nanogenerator (HSR-TENG) is developed focusing on ubiquitous constant working frequency machinery. The unique design of the strip serving as a flexible resonator realizes both soft contact and high and broadband output. The significant factors influencing the 1st-order vibration mode of the strip are developed for realizing the harmonic frequency adaptation to external vibration. The surface treatment of the strip improves the output performance of HSR-TENG by 49.1% as well as eliminates the adhesion effect. The HSR-TENG is able to achieve a voltage output bandwidth of 19 Hz under a vibration strength of 3.0, showing its broadband capability. The peak power density of 153.9 W/m3 is achieved and 12 × 0.5 W light-emitting diodes (LEDs) are successfully illuminated by the HSR-TENG. It can continuously power a temperature sensor by harvesting the actual compressor vibration energy. In brief, the HSR-TENG provides a promising way for constant frequency vibration energy harvesting, so as to achieve in-situ power supply for the WSNs in the vicinity. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) have unique advantages in harvesting low‐frequency irregular mechanical energy, and their output mainly depends on the surface charge density. Inhibiting the loss of triboelectric charges and optimizing the dielectric properties of materials are effective methods for boosting the surface charge density. Several optimization strategies for triboelectric layers, such as surface modification, insertion of intermediate layers, and optimization of dielectric properties, have been reported to improve the output performance of TENGs. In this perspective, first, the material optimization strategies for improving the output performance of TENGs are discussed. Then, in terms of output enhancement, the problems that need to be solved in the future are proposed. Finally, the future roads of high‐performance TENGs for truly realizing efficient mechanical‐energy harvesting are discussed. [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The widespread vibration is one of the most promising energy sources for IoT and small sensors, and broad-frequency vibration energy harvesting is important. Triboelectric nanogenerators (TENGs) can convert vibration energy into electrical energy through triboelectricity and electrostatic induction, providing an effective solution to the collection of broad-frequency vibration energy. Also, the power supply in constrained and compact spaces has been a long-standing challenge. Here, a miniaturized power supply (MPS) based on a broad-frequency vibration-driven triboelectric nanogenerator (TENG) is developed. The size of the MPS is 38 mm × 26 mm × 20 mm, which can adapt to most space-limited environments. The TENG device is optimized through theoretical mechanical modeling for the external stimuli, it can efficiently harvest vibrational energy in the frequency range of 1–100 Hz and has a high output power density of 134.11 W/cm3. The developed device demonstrates its practical application potential in powering small electronics like LEDs, watches, and timers. [ABSTRACT FROM AUTHOR]

The energy harvesting technology for the ubiquitous natural wind enables a desirable solution to the issue of distributed sensors in the bridge environmental sensing Internet of Things (IoT) system being restricted to conventional energy supply. In this work, a self-powered system based on a compact galloping piezoelectric-triboelectric energy harvester (GPTEH) is developed to achieve efficient wind energy harvesting. The GPTEH is constructed on the prototype of a cantilever structure with piezoelectric macro-fiber composite (MFC) sheets and a rectangular bluff body with triboelectric nanogenerators (TENGs). Through a special swing-type structural design with iron blocks inside the bluff body, the GPTEH exhibits preferable aerodynamic behavior and excellent energy conversion efficiency, compared to conventional cantilever kind of piezoelectric wind energy harvester (PWEH). The GPTEH also demonstrates the capability of high output power density (PEH of 23.65 W m−2 and TENG of 1.59 W m−2), superior response wind speed (about 0.5 m s−1), and excellent long-term stability (over 14000 cyclic tests). Furthermore, a power management system is developed to efficiently utilize the output energy from GPTEH to power the sensors and wirelessly transmit environmental data to the terminals. The proposed GPTEH powered system exhibits a great potential for the bridge environmental monitoring and IoT technologies. [ABSTRACT FROM AUTHOR]

Copyright of Micronanoelectronic Technology is the property of Micronanoelectronic Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Triboelectric nanogenerator (TENG) has generated a lot of attention for developing self‐powered/battery‐free technology. These kinds of energy harvesting devices are required for a sustainable future. In this work, the TENG is developed by using the Terminalia Chebula (T. Chebula) biomaterial as tribopositive material. The physiochemical characterizations suggest that T. Chebula has hydroxyl and carbonyl groups which are important to get tribopositivity from the material. The T. Chebula tribopositive material has been tested for the TENG with different electronegative layers such as polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), and polydimethylsiloxane (PDMS). The T. Chebula/PTFE device exhibited a higher output performance. This pair was used for the area and frequency‐dependent studies. In the present case, 16 cm2 device area and 5 Hz frequency conditions show outstanding device performance. Furthermore, the device has been employed for operating low‐power electronic devices such as LEDs and a calculator which operated without any degradation. These results suggested that T. Chebula is a potential tribopositive material for sustainable energy harvesting technology. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG) has gained widespread applications due to their unique ability to convert various forms of mechanical energy, such as wind and tidal energy, into electrical power. However, a critical challenge lies in maintaining high efficiency and stability amid fluctuating environmental temperatures. From a materials perspective, it has been observed that the dielectric constant of the frictional triboelectric layer material is influenced by temperature variations, significantly impacting TENG performance. To address this, our study employed Ba(Cu 0.5 W 0.5)O 3 (BCW)-based ceramic powder to develop temperature-stable materials with a high dielectric constant. These materials were combined with PDMS to create a composite thin film for the TENG frictional triboelectric layer. This novel composite thin film-based TENG exhibited remarkable electrical properties, including an open-circuit voltage (V OC) of 127 V and a short-circuit current (I SC) of 3.16 μA, surpassing conventional PDMS thin film-based TENGs that achieved values of 22 V and 0.65 μA, respectively. From −10 °C to 180 °C, the relative change for V OC is 24.6 %, while for I SC is 28.3 %. Additionally, the BCW-based/PDMS TENG demonstrated the capability to simultaneously power 54 LEDs, showcasing its potential as a versatile self-powered device. Our study not only advanced TENG performance from a material standpoint but also mitigated its sensitivity to environmental temperature, thereby expanding its promising applications in diverse scenarios. [ABSTRACT FROM AUTHOR]

With the development of wearable and wireless electronic devices, the triboelectric nanogenerator (TENG) is attracting interest as a candidate for portable power. Many studies are conducted to increase the surface charge density of the TENG, such as external charge pumping or external electron excitation strategies. However, there are limitations in that another additional external energy source is required. Here, a TENG–capacitor (TC) coupling system that can maximize energy generation and storage efficiency within a limited volume is proposed. Density functional theory calculations indicate that the electric field induced on capacitor increases the fermi energy of positive triboelectric material, resulting in more charge transfer between two triboelectric materials. TC coupling system enhances TENG output performance and the capacitor charging rate in a virtuous cycle. This study provides new insights into TENG structural design and an important guideline for the use of TENG as a portable power source for wearable and wireless applications. [ABSTRACT FROM AUTHOR]

This article explores the use of triboelectric nanogenerators (TENGs) in environmental monitoring and pollutant treatment. TENGs can harness mechanical energy from the environment to power self-contained systems for wastewater purification in remote areas. The article also discusses the use of piezoelectric nanogenerators (PENGs) for energy harvesting and water treatment. Both TENGs and PENGs have the potential to revolutionize wastewater treatment and environmental monitoring, but there are challenges that need to be addressed. The article provides valuable insights into the application of TENGs in environmental monitoring and highlights their potential for sustainable energy harvesting. [Extracted from the article]

Wind energy holds potential for in-situ powering large-scale distributed wireless sensor nodes (WSNs) in the Internet of Things (IoT) era. To achieve high performance in wind energy harvesting, a coaxial counter-rotating triboelectric nanogenerator with lift–drag hybrid blades, termed CCR-TENG, has been proposed. The CCR-TENG, which can work in non-contact and soft-contact modes, realizes low-speed wind energy harvesting through a combination of counter-clockwise rotating lift-type blades and clockwise rotating drag-type blades. Non-contact CCR-TENG realizes low-speed wind energy harvesting at wind speeds as low as 1 m/s. The output of a CCR-TENG, working in soft-contact mode, achieves 41% promotion with a maximum short-circuit current of 0.11 mA and a peak surface power density of 6.2 W/m2 with two TENGs connected in parallel. Furthermore, the power density per unit of wind speed achieves 746 mW/m3·s/m. Consequently, two fluorescent lamps were successfully illuminated and six temperature sensors were continuously lit by the CCR-TENG. The reported CCR-TENG significantly improves low-speed environmental wind energy utilization and demonstrates broad application prospects for in-situ power supply of distributed wireless transmission devices and sensors in the era of the IoT. [ABSTRACT FROM AUTHOR]

Driver's driving behavior and driving style have a crucial impact on traffic safety, capacity, and efficiency, so it is of great significance to monitor the driver's driving behavior and recognize their driving style. In this work, an intelligent driving monitoring system based on a triboelectric nanogenerator and electromagnetic generator is designed. The system consists of a self‐powered pedal motion sensor (SPMS) and an intelligent data processing unit (IDPU), which can monitor driving behavior and recognize driving style. SPMS is used for driving behavior monitoring, which mainly consists of a six‐phase triboelectric nanogenerator (S‐TENG) and a free‐rotating disk electromagnetic generator (FD‐EMG). S‐TENG can recognize information such as pedal movement direction, movement amplitude, and movement speed, and FD‐EMG can realize the function of a self‐powered driver's driving behavior warning. The IDPU includes a numerical calculation system for driving style characteristic variables and a driving style classifier. It can recognize the driving style based on the driving data collected by SPMS. The driving style classifier design is based on a combination of simulated driving experiments and machine learning techniques, and its accuracy is verified through experiments. This work has important potential applications in the field of traffic safety and intelligent driving. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG) has become a promising candidate for wearable energy harvesting and self‐powered sensing systems. However, processing large amounts of data imposes a computing power barrier for practical application. Machine learning‐assisted self‐powered sensors based on TENG have been widely used in data‐driven applications due to their excellent characteristics such as no additional power supply, high sensing accuracy, low cost, and good biocompatibility. This work comprehensively reviews the latest progress in machine learning (ML)‐assisted TENG‐based sensors. The future challenges and opportunities are discussed. First, the fundamental principles including the working mode of ML‐assisted TENG‐based sensor and common algorithms are systematically and comprehensively illustrated, which emphasizes the algorithm definition and principle. Subsequently, the progress of ML methods in the field of TENG‐based sensors is further reviewed, summarizing the advantages and disadvantages of various algorithms in practical examples, and providing guidance and suggestions on how to choose the appropriate methods. Finally, the prospects and challenges of ML‐assisted TENG‐based sensors is summarized. Directions and important insights for the future development of TENG and AI integration is provided. [ABSTRACT FROM AUTHOR]

In the time of Internet of Things (IoT), alternating current electroluminescence (ACEL) has unique advantages in the fields of smart display and human–computer interaction. However, their reliance on external high-voltage AC power supplies poses challenges in terms of wearability and limits their practical application. This paper proposed an innovative scheme for preparing a feather triboelectric nanogenerator (F-TENG) using recyclable and environmentally friendly material. The highest open-circuit voltage, short-circuit current, and transferred charge of SF6-treated F-TENGs can reach 449 V, 63 µA, and 152 nC, which enables easy lighting of BaTiO3-doped ACEL devices. Using a human electrical potential, a single-electrode F-TENG is combined with ACEL device for self-powered fingerprint recognition display. These works achieve self-powered flexible wearable ACEL devices, which are not only efficient and portable but also have good application prospects in the human–computer interaction, functional displays, and wearable electronic devices. [ABSTRACT FROM AUTHOR]

The ocean, with its highly variable and complex meteorological conditions, harbors enormous renewable resources. Triboelectric nanogenerators (TENGs), which possess unique advantages, show exciting prospects in water wave energy collection. How to design and optimize TENGs to cover all characteristic water wave energies and achieve efficient energy utilization is emergent. In this paper, we carefully designed and fabricated a columnar multi-layer sliding TENG (CMLS-TENG) that can harvest water wave energy independent of wave height and direction. Drive rods with a hollow acrylic spherical shell were introduced to deliver wave energy, ensuring that the CMLS-TENG can work in all directions from 0° to 360°. Based on the sliding structure, switching the optimized CMLS-TENG is independent of wave heights. The optimized CMLS-TENG can achieve a total power density of 730 mW/m3 at a wave height of only 4.8 cm regardless of wave direction, which can illuminate multiple light-emitting diodes (LEDs) to provide lighting and provide power to a watch and a hygrometer for temperature and humidity monitoring. This work provides new choices and hopes for the effective collection of full-range water wave energy. [ABSTRACT FROM AUTHOR]

The current field of human‐machine interaction (HMI) and electronic skin (e‐skin) is confronting challenges associated with energy supply, sensitivity, and biocompatibility. Traditional HMI systems, though rich in features, are constrained in their applications in the medical and wearable technology sectors due to their rigid structure and reliance on third‐party power inputs. Triboelectric nanogenerators (TENGs) based on natural materials are emerging as a focal point of research in this domain, attributed to their self‐powering capabilities, flexibility, and biocompatibility. These natural material‐based TENGs emulate the mechanical and biological characteristics of human skin, adapt to various body shapes and movements, and offer an efficient and reliable solution for the precise detection and analysis of complex, subtle physiological signals, thereby fostering innovations in wearable devices and robotic technology. This article provides a comprehensive review of recent advancements in natural material‐based TENGs, detailing the materials employed, including proteins, chitosan, and cellulose. It encapsulates their applications in the realms of electronic skin and HMI. Finally, the challenges confronted by natural material‐based TENGs are outlined and future trajectories for development in this burgeoning field are projected. [ABSTRACT FROM AUTHOR]

In drilling operations, measuring vibration parameters is crucial for enhancing drilling efficiency and ensuring safety. Nevertheless, the conventional vibration measurement sensor significantly extends the drilling cycle due to its dependence on an external power source. Therefore, we propose a vibration-accumulation-type self-powered sensor in this research, aiming to address these needs. By leveraging vibration accumulation and electromagnetic power generation to accelerate charging, the sensor's output performance is enhanced through a complementary charging mode. The experimental results regarding sensing performance demonstrate that the sensor possesses a measurement range spanning from 0 to 11 Hz, with a linearity of 3.2% and a sensitivity of 1.032. Additionally, it exhibits a maximum average measurement error of less than 4%. The experimental results of output performance measurement indicate that the sensor unit and generator set exhibit a maximum output power of 0.258 μW and 25.5 mW, respectively, and eight LED lights can be lit at the same time. When the sensor unit and power generation unit output together, the maximum output power of the sensor is also 25.5 mW. Furthermore, we conducted tests on the sensor's output signal in conditions of high temperature and humidity, confirming its continued functionality in such environments. This sensor not only achieves self-powered sensing capabilities, addressing the power supply challenges faced by traditional downhole sensors, but also integrates energy accumulation with electromagnetic power generation to enhance its output performance. This innovation enables the sensor to harness downhole vibration energy for powering other micro-power devices, showcasing promising application prospects. [ABSTRACT FROM AUTHOR]

The inclination angle is an important factor for slope deformation monitoring. This paper introduces a self-powered pendulum inclination sensor (PI-TENG) based on triboelectric nanogenerator, which can effectively monitor slope deformation. PI-TENG adopts raster-sliding mode as the main structure. The fabricated PI-TENG, based on a raster-sliding working mode, using the linear relationship between the rotation angle of the monitoring object and the number of output pulses to establish an intuitive rotation signal mapping, which can realize self-powered monitoring of the rotation direction and angle not being affected by the environment (such as temperature and humidity). The corresponding minimum resolution of PI-TENG is 3° and can be further improved by increasing the number of Nylon grids on the stator. Importantly, the sensor has a simple structure and low price, and can realize self-powered monitoring without additional power supply. This work provides new ideas for monitoring slope deformation and early warning of landslides. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) utilize the synergetic effect of triboelectrification and electrostatic induction to guide electrons through an external circuit, enabling low‐frequency mechanical and biomechanical energy harvesting and self‐powered sensing. Integrating 2D material with a high specific surface area into flexible ferroelectric polymers such as polyvinylidene difluoride (PVDF) has proven to be an efficient strategy to improve the performance of TENG devices. Scalable fabrication of graphene‐integrated PVDF nanocomposite fiber using thermal drawing process is demonstrated for the first time in this study. The open‐circuit voltage and short‐circuit current show 1.41 times and 1.48 times improvement with the integration of 5% graphene in the PVDF fibers, respectively. The TENG fabric shows a maximum power output of 32.14 µW at a matching load of 7 MΩ and a power density of 53.57 mW m−2. The fibers exhibit excellent stability in harsh environmental conditions such as alkaline medium, high/low temperature, multi‐washing cycle, and long‐time usage. [ABSTRACT FROM AUTHOR]

Intelligent face masks play crucial roles in health monitoring and disease prevention, having attracted huge attention in recent years. However, most of the current intelligent face masks focus on monitoring single physical signal, which were unable to provide comprehensive information. Herein, an intelligent face mask with airflow and temperature sensing abilities, high-efficiency filtration and excellent antibacterial activity was proposed. The real-time airflow monitoring was realized by a triboelectric nanogenerator (TENG), which was composed of electrospun nanofibrous membrane and polydimethylsiloxane (PDMS) composite film. The fabricated electrospun nanofibrous membrane simultaneously played roles as tribo-positive material, filter and antibacterial membrane. The PDMS composite film prepared by co-blending and surface modification was applied as tribo-negative material. It was found that the combination of co-blending and surface modification enhanced the tribo-negative property of the PDMS film, resulting in an increment of output performance of TENG. The TENG integrated into a face mask could monitor respiratory rate and respiration intensity in real time. Additionally, the temperature sensing was achieved by a serpentine PDMS/laser-induced graphene temperature sensor. The temperature sensor exhibited a temperature coefficient of resistance of 0.316% °C−1, which could detect subtle temperature variations. Furthermore, the electrospun nanofibrous membrane exhibited excellent filtration performance and antibacterial activity. Therefore, the prepared intelligent face mask showed promising potential for healthcare applications. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) are energy generation devices that naturally convert mechanical movements into electrical energy through both triboelectric and electrostatic effects. The electricity generation capacity of silicone/boron minerals‐based composite and glass fiber‐based vertical contact separation mode TENGs enhances by adjusting the triboelectrification characteristics by embedding natural boron minerals (NBO) such as borax, colemanite, and ulexite additives. Considering the generated voltages, the NBO‐doped silicone and glass fiber‐based TENGs offer the maximum performance with 2.5 wt% borax, 7.5 wt% colemanite, and 5 wt% ulexite. The highest power density of corresponding NBO‐doped silicone glass fiber TENGs finds as 25.4, 26.03, and 32.03 W m−2, respectively. This work demonstrates that using boron significantly improves the TENG's power and charging capacities fabricated with silicone and glass fiber. Thus, the clean and safe generation of energy will contribute to the reduction of fossil fuel consumption and help protect the environment. [ABSTRACT FROM AUTHOR]

Mechanical equipment is ubiquitous in industrial production, and the vibration energy generated by its operation usually cannot be effectively harvested, resulting in huge energy waste. Meanwhile, real‐time monitoring of machine operation can be achieved by collecting vibration information. Indeed, vibration energy harvesting and vibration monitoring are of great significance for the development of green energy and machine fault diagnosis. As an emerging power generation technology, triboelectric nanogenerator (TENG) has shown extraordinary potential in the field of vibration energy harvesting and vibration monitoring. First, the theoretical basis, working modes, and triboelectric materials are described. Then, TENG devices for vibration energy harvesting are classified and introduced based on the structural characteristics, and the main advantages and disadvantages are compared. Furthermore, the current research progress of a self‐powered vibration monitoring system based on TENG is introduced. Finally, the shortcomings of triboelectric nanogenerators in this field are analyzed and summarized, and future research directions and application scenarios are prospected. [ABSTRACT FROM AUTHOR]

Ocean wave energy is one of the important renewable energy sources. However, random, low‐frequency, and micro‐amplitude characteristics of ocean waves make it difficult for traditional electromagnetic generators to collect wave energy efficiently. The emergence of triboelectric nanogenerator (TENG) provides an extremely effective technical means for the collection of low‐frequency and micro‐amplitude wave energy. In this work, a non‐contact turntable‐structured oscillating water column TENG (OWC‐TENG) is designed by combining an OWC wave energy conversion mechanism with a TENG for the first time. The OWC is optimized through simulation experiments according to the principles of ship hydrostatics and wave theory. The output performances of the OWC‐TENGs with different structural parameters under different water wave excitation conditions are then tested. The TENG delivers a maximum output current of 55.45 µA and an output power of 5.28 mW, which corresponds to a power density of 114.8 W m−3, enabling a stable power supply for small sensors at sea. This work provides a new solution to the efficient collection of low‐frequency micro‐amplitude ocean wave energy for powering various offshore equipments, presenting broad application prospects in ocean blue energy development and offshore Internet of Things. [ABSTRACT FROM AUTHOR]

With the rapid advances in the Internet of Things, it is possible to construct a self-charging power system integrating a triboelectric nanogenerator (TENG) and supercapacitor (SC), which represents an excellent tool for simultaneous conversion and storage of distributed environmental energy. In particular, the well-researched Ti3C2T x MXene materials for triboelectric nanogeneration lack high and stable power density, mainly due to the charge dissipation effect on their surface. Herein, the effectiveness of MXenes is enhanced by encrusting TiO2 on the inner and outer surfaces via a hydrothermal method. TiO2, which has inherent dielectric properties, could serve the dual function of electron trapping/blocking and surface polarization, mitigating the diffusion and drifting of surficial tribo-charges and thus increasing output TENG performance. An integrated TENG based on MXene/TiO2 composites with a TiO2 concentration of 3 mM has a higher output voltage than a pristine MXene-based TENG (110 V, a 1.83-fold increase) and achieves a maximum instantaneous power density of ∼1440 mW m−2. TiO2 is also conductive to pseudo-faradaic reactions, and the integrated MXene/TiO2 based symmetric SC exhibits an enhanced specific capacitance of 231.08 F g−1 at 1 A g−1, which is 4.52 times that of pristine MXene, with a maximum energy density of 12.74 W h kg−1 at a power density of 483.06 W kg−1. Finally, utilizing polyimide sheets as substrates, the flexible self-charging power system was integrated: the TENG charges the SC up to 0.8 V with a charging/discharging time of 37 s/40 s, showing great promise for the demands of flexible and self-powered electronics. [ABSTRACT FROM AUTHOR]

We investigated the polarity dependence of a capacitive energy management circuit in a triboelectric nanogenerator (TENG) power system. In a half-wave rectifying circuit, the Simulation Program with Integrated Circuit Emphasis and analytical models show that the charge dump to the load varied depending on the polarity of the rectifying circuit even with the same charge output from TENG. Depending on the polarity of the rectifying circuit, a fast saturation of the direct current (DC) output voltage or a high DC output voltage was obtained. Experiments with a half-wave rectifier and Bennet doubler confirmed our simulation and theoretical results. The charge dump from the minimum capacitance of the separated TENG to the load capacitance and the charge dump from the maximum capacitance of the contacted TENG to the load resulted in asymmetric charging behavior. We concluded that it is necessary to analyze the TENG and the capacitive energy management circuit as a single system rather than considering them as independent units in the rectifying circuit of the TENG. This work can provide insights for the design of triboelectric energy harvesting systems. [ABSTRACT FROM AUTHOR]

The increasing number of IoT devices has led to more electronic waste production, which harms the environment and human health. Self-powered sensor systems are a solution, but they often use toxic materials. We propose using biocompatible peanut skin as the active material for a self-powered humidity sensor (PSP-SPHS) through integration with a peanut-skin-based triboelectric nanogenerator (PSP-TENG). The PSP-TENG was characterized electrically and showed promising results, including an open circuit voltage (162 V), short circuit current (0.2 µA), and instantaneous power (2.2 mW) at a loading resistance of 20 MΩ. Peanut skin is a great choice for the sensor due to its porous surface, large surface area, eco-friendliness, and affordability. PSP-TENG was further used as a power source for the PSP-humidity sensor. PSP-SPHS worked as a humidity-dependent resistor, whose resistance decreased with increasing relative humidity (%RH), which further resulted in decreasing voltage across the humidity sensor. This proposed PSP-SPHS exhibited a good sensitivity (0.8 V/RH%), fast response/recovery time (4/10 s), along with excellent stability and repeatability, making it a potential candidate for self-powered humidity sensor technology. [ABSTRACT FROM AUTHOR]

With the vigorous development of the Internet of Things, 5G technology, and artificial intelligence, flexible wearable sensors have received great attention. As a simple and low-cost power supply in wearable sensors, the triboelectric nanogenerator (TENG) has a wide range of applications in the field of flexible electronics. However, most polymers are thermally poor conductors (less than 0.1 W/(m·K)), resulting in insufficient heat dissipation performance and limiting the development of TENG. In this study, a high-performance non-woven fabric TENG with strong thermal conductivity (0.26 W/m·K) was achieved by introducing ZrB2 into the polyurethane (PU) matrix. The excellent output performance with an open circuit voltage (Voc) of 347.6 V, a short circuit current (Isc) of 3.61 μA, and an accumulated charge of 142.4 nC endows it with good sensitivity. The electrospun PU/ZrB2 composites exhibit excellent sensing performance to detect body movements in situ, such as pressing, clapping, running, and walking. Moreover, the generated power can light up 224 LED bulbs as a demonstration of self-powering ability. [ABSTRACT FROM AUTHOR]

[Display omitted] • FC@NF and T@CF were prepared by LBL self-assembly and soaking methods, respectively. • Fire-retardant performance and mechanism of FC@NF were investigated. • FCF-TENG was fabricated for self-powered sensing in fire scenarios. The fabrics commonly used in architectural decorative materials pose significant fire hazards due to their flammability and rapid fire spread. Moreover, the traditional fire-alarm systems may fail to function properly in complex fire environments owing to power supply disruptions. In this study, we developed a low-cost and eco-friendly flame-retardant conductive fabric-based triboelectric nanogenerator (FCF-TENG) by integrating flame-retardant conductive nylon fabric and polytetrafluoroethylene soaked cotton fabric. This nanogenerator exhibits excellent flame-retardant properties and remarkable energy-harvesting capabilities. The nylon fabric, treated with layer-by-layer self-assembly method, possesses outstanding self-extinguishing capability and melt-dripping resistance. Additionally, the electrical performance of FCF-TENG significantly improves, with a 10-fold boost in conductivity, and the open-circuit voltage increases by 84% to 92 V. Besides, by incorporating the rectifier circuit, the FCF-TENG is capable of completely charging a 1 μF capacitor within 30 s. Furthermore, the FCF-TENG was successfully applied as a self-powered sensor in the fire-alarm system and served as a safety exit indicator for evacuees and fire rescue. This work presents an effective and innovative application of multifunctional smart textiles for energy harvesting and self-powered sensing. [ABSTRACT FROM AUTHOR]

As the increasing scarcity of fossil fuels and the ever‐present need to address environmental concerns are faced, the development of efficient and sustainable energy harvesting techniques gains more and more significance. The liquid–solid triboelectric nanogenerator (TENG) has emerged as a promising solution for harvesting mechanical energy in water. Although the liquid–solid contact electrification technique is studied by numerous researchers, there is still a need to enhance energy harvesting efficiency in liquid–solid TENG. This comprehensive review discusses recent advances in kinetic energy harvesting from water, focusing on the solid–solid and liquid–solid interaction mechanisms when using TENGs as an energy conversion medium. The review summarizes the recent developments in structure design and material improvements, as well as hybridization with other generators as methods of enhancing the output performance of TENG. Besides discussing advancements of TENG, the potential impact and future challenges of liquid–solid TENG are highlighted. This paper provides insight into the current state of knowledge and the future directions of research in the field of liquid–solid TENG energy harvesting. [ABSTRACT FROM AUTHOR]

Downhole drilling tool vibration measurement is crucial for drilling exploration safety, so real-time monitoring of vibration data is required. In this research, a honeycomb triboelectric nanogenerator (H-TENG) capable of adapting to various downhole environments is proposed. It can measure the frequency of downhole drilling equipment's vibrations and transfer mechanical energy to electrical energy for use in powering other low power downhole meters. In order to preliminarily verify the possibility of sensors used for vibration measurement of downhole drilling tools, we built a simulated vibration platform to test the sensing performance and vibration energy collection performance of H-TENG. According to the testing results, the measurement range of vibration frequency and amplitude are 0 to 11 Hz and 5 to 25 mm, respectively, and the corresponding measurement errors are less than 5% and 6%, respectively. For vibrational energy harvesting, when four sensors are wired in series with a 107 resistance, the maximum power is approximately 1.57 μW. Compared to typical methods for measuring downhole vibration, the honeycomb triboelectric nanogenerator does not need an external power source, it has greater reliability and output power, and it can vary its shape to adapt to the complicated downhole environment. In addition, the H-TENG can be combined freely according to the diameter of the drill string, and even if one sensor unit is damaged, the other units can still be used normally. [ABSTRACT FROM AUTHOR]