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Harnessing energy from underwater bubbles has garnered significant attention, particularly for powering off‐grid circuitry. However, the efficiency of bubble‐driven liquid‐solid interface charge transfer remains low. This research unveils a phenomenon: accelerated bubble slippage enhances liquid‐solid interfacial charge transfer. Building upon this discovery, a pulse bubble‐based power generation technique is proposed, achieving an energy density of 24.2 mJ L−1 generated by pulsed bubbles. The crux of pulse bubble power generation lies in the precise control of impact velocity. By meticulously regulating the impact kinetic energy of bubbles, the accumulated potential energy of multiple small bubbles is converted into instantaneous pulse kinetic energy. A typical pulse bubble is controlled within a 72 ms timeframe, unleashing a surge of energy that can directly illuminate 400 light‐emitting diodes. This approach represents a groundbreaking advancement in underwater energy harvesting technology, dramatically expanding its potential applications. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) combine contact electrification and electrostatic induction effects to convert waste mechanical energy into electrical energy. As conventional devices contribute to electronic waste, TENGs based on ecofriendly and biocompatible materials have been developed for various energy applications. Owing to the abundance, accessibility, low cost, and biodegradability of biowaste (BW), recycling these materials has gained considerable attention as a green approach for fabricating TENGs. This review provides a detailed overview of BW materials, processing techniques for BW‐based TENGs (BW‐TENGs), and potential applications of BW‐TENGs in emerging bioelectronics. In particular, recent progress in material design, fabrication methods, and biomechanical and environmental energy‐harvesting performance is discussed. This review is aimed at promoting the continued development of BW‐TENGs and their adoption for sustainable energy‐harvesting applications in the field of bioelectronics. [ABSTRACT FROM AUTHOR]

Ion‐gels, with inherent flexibility, tunable conductivity, and multi‐stimulus response, have attracted significant attention in flexible/wearable electronics. However, the design of ion‐gels that exhibit both strength and toughness is challenging. In this study, a novel ion‐gel design is proposed that mimics the hierarchical meshing structure of leaves in combination with ion hybridization. Polyacrylamide (PAM) is incorporated in TEMPO oxidized cellulose nanofibers (TOCNFs) clusters by in situ polymerization, generating a hydrogel with micro/nanoscale entangled networks. Replacement of water by a metal halide ionic liquid ([BMIm]ZnxCly) in the hydrogel resulted in the formation of an ion hybrid network with supramolecular interactions. The integration of the PAM/TOCNF polymer network with [BMIm]ZnxCly resulted in ion‐gels with high strength (5.9 MPa), toughness (22 MJ m−3), and enhanced elastic modulus (30 MPa) combined with non‐flammability, heat and cold resistance. While having fast responsiveness (36 ms) of sensing signal and stability of power supply even at 4000 cycle collisions. Stable signal output even at high (200 °C) /sub‐zero temperatures. The proposed strategy offers a new approach to the material design of flexible/wearable electronics. [ABSTRACT FROM AUTHOR]

Recently through the synergetic utilization of triboelectrification, electrostatic induction, and electrostatic discharge, a novel dual‐functional triboelectric nanogenerator (DF‐TENG) has been developed, which can not only generate a motion‐responsible alternating current/ direct current output but also provide a higher performance compared to traditional TENGs. However, further improvements in performance and lifespan are crucial and remain challenging for the future large‐scale application of this new‐type TENG. Herein, a novel bioinspired self‐lubricating prototype is presented (BS‐TENG), which employs a porous polyurethane (PU) matrix impregnated with a low‐viscosity dielectric lubricant. In response to external mechanical stimuli, the BS‐TENG can "secrete" pre‐stored lubricant to partially fill micro‐gaps between tribo‐layers, thus forming self‐lubrication. This self‐lubricating mechanism not only elevates the electrostatic discharge threshold between tribo‐layers to maximize charge accumulation, thereby facilitating efficient energy release through electrostatic discharge for enhanced power output, but also significantly reduces material abrasion and realizes superior output durability. Benefiting from this effect, the BS‐TENG delivers an average power density of up to 4.6 W m−2, with extraordinary stability to retain 99% of its initial output even after over 60 000 cycles. This work provides a straightforward and effective strategy for realizing high‐performance and long‐stability TENGs, paving the way for their practical applications. [ABSTRACT FROM AUTHOR]

Functional triboelectric insoles hold promise for advancing self‐powered wearable technologies. However, their durability is compromised by continuous compressive forces and friction, leading to surface abrasion and material fracturing. To address these challenges, an innovative fabric‐reinforced structure combined with a dual‐L backrest design is developed that enhances anti‐fracture capabilities and electric outputs while enabling AI‐empowered motion monitoring. Polydimethylsiloxane (PDMS) is used as the negative triboelectric material with a dual‐L backrest design, while insulated copper wire (icuW) serves as the positive triboelectric material with an annular structure design. These components are intricately nested to enable a multilayered friction pairing. The fabric‐reinforced structure demonstrates excellent compressive rebound resilience, withstanding forces of at least 1000 N. The functional insole, featuring a fabric‐reinforced dual‐L backrest structure (FRdL‐insole), efficiently harvests biomechanical energy with a peak power of 8214 µW and maintains highly consistent performance after 10 washing cycles and 60 000 durability tests. It can power portable electronic devices such as digital watches, calculators, hygrometers, and LEDs. Enhanced with machine learning algorithms, the FRdL‐insole processes sensor signals to monitor human movements, accurately identifying seven distinct motions. This positions the insole as a smart, real‐time, self‐powered tool for activity recognition, showcasing its potential in intelligent wearable technology. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG) offers a novel approach for converting high‐entropy mechanical energy into electrical energy, yet achieving high charge density remains critical. Optimizations using dielectrics with high specific capacitance have mitigated air breakdown, but charge loss within dielectrics persists as a limiting factor. Here, based on poly(vinylidene fluoride–trifluoroethylene–chlorofluoroethylene) (P(VDF‐TrFE‐CFE)) with high specific capacitance, (P(VDF‐TrFE‐CFE)) composites’ trap density and energy are engineered using high‐polarity interfaces from barium titanate (BTO) nanoparticles and dense chain segment stacking induced by electrostatic interaction with polyetherimide (PEI) to enhance charge retention capability. With modified high interfacial traps, an ultrahigh charge density of 9.23 mC m−2 is achieved in external charge excitation (ECE) TENG using 0.2 vol% PEI/P(VDF‐TrFE‐CFE) film, marking the highest charge density reported for single‐unit TENGs. This work provides novel material strategies for high‐performance TENGs, paving the way for their large‐scale practical applications. [ABSTRACT FROM AUTHOR]

A triboelectric nanogenerator (TENG) is an emerging energy harvesting technology that utilizes the combination of triboelectrification and electrostatic induction to collect wasted mechanical energy and convert it into electricity. In this work, an aluminosilicate (AS)-based composite, considered as a potential alternative to cement material, has been developed for the fabrication of TENGs. Herein, the AS material is synthesized through the alkali activation of fly ash using a mixture of sodium hydroxide (NaOH) and sodium silicate (Na 2 SiO 3) solutions as activating agents. The electrical output of AS TENGs can be optimized by tuning the liquid-to-solid powder (L/S) ratio during the fabrication of AS composites. The AS composites fabricated at different L/S ratios exhibit the variations in dielectric properties, surface morphology and microstructure. It is found that a high dielectric constant is not the only requirement for achieving optimal TENG output performance. The contribution of dielectric properties and microstructures of the AS composites on TENG performance is discussed. The AS composite with an optimal L/S ratio of 0.5 results in the highest TENG power output density of 2.78 W/m2. Additionally, the versatility of AS TENG to harvest mechanical energy and its application as a power source for portable electronic device are demonstrated. This research has proposed the promising aspect of AS composites as alternative construction materials capable of harvesting mechanical energy, which is essential for the development of green and sustainable power sources. [ABSTRACT FROM AUTHOR]

The performance of composite-based triboelectric nanogenerators (C–TENGs) was significantly enhanced through laser surface patterning and graphite coating. The laser etching process produced accurate and consistent patterns, increasing surface area and improving charge accumulation. SEM imagery confirmed the structural differences and enhanced surface properties of the laser-etched C–TENGs. Graphite fibers further augmented the contact surface area, enhancing charge accumulation and diffusion. Experimental results demonstrated that the optimized C–TENGs, especially those with line patterns and graphite coating, achieved a maximal 98.87 V open-circuit voltage (VOC) and a 0.10 µA/cm2 short-circuit current density (JSC) under a 20 N external force. Environmental tests revealed a slight decrease in performance with increased humidity, while long-term stability tests indicated consistent performance over three weeks. Practical application tests showed the potential of C–TENGs integrated into wearable devices, generating sufficient energy for low-power applications, thereby highlighting the promise of these devices for sustainable energy solutions. [ABSTRACT FROM AUTHOR]

Implantable electrical neurostimulators offer a promising avenue for treating neurological disorders. However, their dependency on a finite battery life limits their long‐term utility. Emerging transcutaneous ultrasound‐driven triboelectric nanogenerator (TENG) techniques provide solutions for converting external ultrasound waves into internal electricity. This study proposes an implantable ultrasound‐driven TENG (IU‐TENG) using polyether ether ketone (PEEK) for its exceptional stability inside a human body and acoustic impedance compatibility with human tissues. This IU‐TENG remarkably surpasses traditional titanium‐based encapsulation, resulting in a 99.94% efficiency in ultrasound transmission. In addition, PEEK contains numerous electron‐donating functional groups, making it suitable for TENG applications, particularly as a positive triboelectric layer. The device exhibits robust voltage outputs, reaching up to 11.50 and 8.75 V in water and in vivo, respectively, under body‐safe ultrasound intensities. Moreover, its ability to sustain a stable electrical output for over 300 min emphasizes the durability and mechanical resilience of PEEK. In vivo mouse models and ex vivo porcine tissue trials demonstrate the effectiveness of the IU‐TENG in nerve stimulation, showing its potential in medical treatments, enhancing the functionality and longevity of implantable medical devices. [ABSTRACT FROM AUTHOR]

Wearable electronics with multi‐functionalities are widely utilized in various domains, including everyday living, healthcare, military training, and sports. Advances in flexible electronic technology, new materials, artificial intelligence technology, and sensor technology have accelerated the rapid development of smart wearable devices toward multifunctional and highly integrated trends. The energy supply technology based on the human‐body energy harvesting method endows wearable, multifunctional electronic devices with sustainable, renewable, and self‐powered characteristics, which proposes a solution strategy for the function expansion and energy supply of wearable devices. Herein, this paper discusses recent research on various methods of harvesting human body energy and wearing parts respectively, focusing on the new materials, structures, and processes involved in the representative studies, as well as the impact on energy harvesting and output, and functional applications. Furthermore, the challenges and obstacles faced in the creation of wearable multifunctional devices based on human self‐sufficiency and propose solution strategies to propel them in order to advance the creation of the next wave of intelligent wearable technology are also discussed. [ABSTRACT FROM AUTHOR]

The hunt for sustainable and efficient energy harvesting and storage devices has driven significant interest in triboelectric nanogenerators (TENGs) as potential alternatives to traditional batteries for powering electronic devices. However, the development of biodegradable TENGs remains a formidable challenge. This study presents the preparation of a tribopositive material entirely composed of biodegradable poly(butylene adipate-co-terephthalate) (PBAT) polymer enhanced with CoFe2O4 (CF) nanoparticles. The CF nanoparticles, synthesized via the combustion method, were incorporated into the PBAT matrix through solvent casting to form films with varied filler content (0.2, 0.4, 0.6, 0.8, and 1 g). The CF nanoparticles structural, surface, and electrical properties were characterized using XRD and FTIR spectroscopy. At the same time, the morphology of the nanomaterials and their composites was analyzed by scanning electron microscopy. Specifically, the 0.8 g PBAT-CF TENG demonstrated superior performance, achieving an output voltage of 45.45 V and a current of 4.5 µA. Subsequent electrical studies, including charging commercial capacitors (1.0 to 47 μF) and powering LEDs and calculators, underscored the device's efficiency. The PBAT-CF TENG also effectively generated voltage and current signals from physical activities like walking and jumping. This innovative approach highlights the potential for biodegradable, high-performing, self-powered flexible electronics, and wearable devices, paving the way for sustainable technological advancements. [ABSTRACT FROM AUTHOR]

A unique oscillating wind-driven triboelectric nanogenerator (OWTENG) based on the sphere's vortex-induced vibration (VIV) behavior is proposed in this study, which can harvest wind energy across a multitude of horizontal directions. With the Euler-Lagrange method, the coupled governing equations of the OWTENG are established and subsequently validated by experimental tests. The vibrational properties and output performance of the OWTENG for varying wind speeds are analyzed, demonstrating its effectiveness in capturing wind energy across a broad range of wind speeds (from 2.20 m/s to 8.84 m/s), and the OWTENG achieves its peak output power of 106.3 µW at a wind speed of 5.72 m/s. Furthermore, the OWTENG maintains a steady output power across various wind directions within the speed range of 2.20 m/s to 7.63 m/s. Nevertheless, when the wind speed exceeds 7.63 m/s, the vibrational characteristics of the sphere shift based on the wind direction, leading to fluctuations in the OWTENG's output power. This research presents an innovative approach for designing vibrational triboelectric nanogenerators, offering valuable insights into harvesting wind energy from diverse directions and speeds. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) made from biocompatible materials serve as promising integrated power sources for portable wearable electronics due to many advantages such as lightweight, high flexibility, simple technique, and excellent breathability. In this work, we report the fabrication of electrospun polycaprolactone micro-nanofiber films (s-PCL) and convex-microdome-patterned polydimethylsiloxane (c-PDMS) utilizing electrospinning and micromolding techniques. These materials, s-PCL and c-PDMS, are utilized as positively and negatively charged tribosurfaces, respectively, in the development of a bioTENG device. The developed TENG device can generate a superior power output of 2 mW with an open-circuit voltage (VOC) of 188 V and short-circuit current (ISC) of 18.5 µA, even under a low triggering frequency of 5 Hz. In addition, TENG possesses outstanding durability and output performance stability over a continuous operation of nearly 16,000 cycles. Furthermore, the TENG demonstrates its capacity to harvest mechanical energy and convert it into electricity, capable of directly illuminating more than 100 LEDs. The electrospun s-PCL- and c-PDMS-based TENG can be considered for self-powdered wearable devices attached to fingers, wrists, feet, and other human body parts. [ABSTRACT FROM AUTHOR]

Ocean wave energy represents a widely distributed and abundant clean, renewable energy source. However, its efficient harnessing remains a challenge. In this study, a triboelectric‐electromagnetic hybrid generator of a Ferris‐wheel‐like structure (FWS‐TEHG) with magnetic repulsion assistance is proposed to effectively enhance the collection of low‐frequency and low‐amplitude water wave energy. The Ferris‐wheel shell and the internal rotator are designed with a phase difference to heighten the swing amplitude, while the introduction of magnetic repulsion augments the motion frequency. The device has demonstrated excellent performance in low‐frequency conditions, from laboratory to ocean wave tests. Operating at a frequency of 0.5 Hz and a swing angle of 12° on a six‐freedom platform, it lights up 64 LEDs with a power rating of 2 W. Triggered by simulated water waves with a frequency of 1 Hz, the FWS‐TEHG charges a 19 mF capacitor at an average charging rate of ≈0.58 W h−1, powering a water‐level alarm. In oceanic conditions, the FWS‐TEHG effectively harvests energy from water waves by exhibiting an output frequency approximately four to five times higher than that of the primary frequency of ocean waves, thus enabling it to power electrical devices such as temperature–humidity meters efficiently. This study provides a valuable reference for advancing the practical application of nanogenerators in natural ocean environments. [ABSTRACT FROM AUTHOR]

The ocean harbors an abundance of resources, encompassing not only wave energy but also considerable wind energy. Triboelectric nanogenerator (TENG), as a technology for harvesting low‐frequency, high‐entropy mechanical energy, has shown distinct advantages in the collection and application of marine and wind energy. This study introduces a triboelectric Wind and wave energy harvester (TWWEH), an energy collector based on TENG, which can be used to harness wind and wave energy. The TWWEHs comprise a wind‐driven TENG (W‐TENG) for wind energy collection and a ring‐shaped TENG (R‐TENG) for wave energy collection. The proposed vertically integrated TENG architecture enhances spatial utilization rate. Under oscillatory conditions of 0.8 Hz and ±30°, the R‐TENG generates a peak power of 0.20 mW. While at a wind speed of 10 m s−1, a peak power of the W‐TENG can reach 0.11 mW. This research provides a promising solution to harvest wave and wind energy from the ocean, offering significant potential applications in establishing self‐powered oceanic assessment and meteorological systems. [ABSTRACT FROM AUTHOR]

The highly sensitive and power efficient tactile sensors can provide grippers with vertical and shear forces from interactions with objects. In an ocean environment with low visual distance and high noise, sea otters can rely on their palms to accurately identify and grasp target objects without damage. Inspired by the structure of the sea otter's palm, this paper proposes a distributed liquid metal-based three-dimensional biomimetic underwater triboelectric palm-like tactile sensor (UPTS) for feedback-controlled grippers. The device is mainly composed of a flexible shell, a flexible cover, a flexible support, a triboelectric sensing unit and a fixed shell. The force acting on the flexible cover causes the flexible cover and sensing unit to deform, so that the sensing unit undergoes a contact-separation process, thereby generating an electrical signal. UPTS has the capability to identify the magnitude and direction of force, with a direction recognition error angle within 5 degrees. Additionally, it can distinguish the hardness and shape of objects, achieving an accuracy rate of 100% and 99.75% respectively for the tested objects. The results indicate that UPTS can provide force feedback for underwater grippers, thereby assisting the grippers in better completing salvage task. [ABSTRACT FROM AUTHOR]

Although biopolymers have been widely utilized as triboelectric materials for the construction of self-powered sensing systems, the annihilation of triboelectric charges at high temperatures restricts the output signals and sensitivity of the assembled sensors. Herein, a novel chitosan/montmorillonite/lignin (CML) composite film was designed and employed as a tribopositive layer in the assembly of a self-powered sensing system for use under hot conditions (25–70°C). The dense contact surface resulting from the strong intermolecular interaction between biopolymers and nanofillers restrained the volatilization of induced electrons. The optimized CML-TENG delivered the highest open-circuit voltage (Voc) of 262 V and maximum instantaneous output power of 429 mW/m2. Pristine CH-TENG retained only 39% of its initial Voc at 70°C, whereas the optimized CM5L3-TENG retained 66% of its initial Voc. Our work provides a new strategy for suppressing the annihilation of triboelectric charges at high temperatures, thus boosting the development of self-powered sensing devices for application under hot conditions. [ABSTRACT FROM AUTHOR]

Significant efforts are devoted to optimizing the efficiency of triboelectric energy harvesting systems, particularly through the design of an advanced power management system (PMS) for Triboelectric Nanoenerators (TENGs). A critical aspect of PMS is the design and control of switches. However, existing switches face significant limitations. For spark switches, precise control cannot be achieved, and electronic switches can only operate at voltages below several hundred volts which is limited by the risk of electrical breakdown. To address these limitations, a hybrid electronic‐spark switch power management system (HESS) is proposed. HESS changes the connection of capacitors from parallel to series by deploying a maximum voltage tracking switch components at the peak voltage point, resulting in a much‐elevated voltage level to activate the spark switch. This approach achieves precise control of the spark switch for the first time and significantly reduces the operating voltage of electronic switches. Through simulation and experimental verification, HESS achieves the control at a voltage level of 1.8 kV for spark switch, with an electrical component breakdown voltage of only 450 V. The power density of the HESS is 29.8 mW Hz−1 m−2, which is a new record for electronic switches. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) provide promising power supply solutions by transforming mechanical energy into electrical energy. However, enhancing electrical performance of TENGs is essential for their widespread practical applications and commercialization. In this study, we fabricated TENGs in vertical contact‐separation mode using a tribopositive material—polyvinyl alcohol (PVA) slime—which is biocompatible, flexible, and wearable, decorated with graphene nanoplatelets (GnPs), and paired with tribonegative silicone. We analyzed the correlation between the electrical performance of the TENGs and the inherent triboelectric properties of the constituent material, including the evaluation of surface roughness, the measurement of the contact potential difference (CPD), and the material's dielectric constant. The incorporation of GnPs increased the dielectric constant of the composite material and its electron‐donating tendency, thus, increasing the contact potential difference. The GnPs concentration of 1 wt% was identified as the optimal value, resulting in a 42% increase in power density. The 1 wt% GnPs@PVA&Silicone TENG exhibited an open‐circuit voltage of 718 V and a peak power density of 15.3 W/m2. This study sheds light on enhancing the energy harvesting efficiency of TENGs through the utilization of biocompatible tribopositive and tribonegative materials. [ABSTRACT FROM AUTHOR]

Flexible strain sensors capable of acquiring tiny mechanical signals and attaching to various irregular surfaces are becoming prevalent in physiological measurement, soft robotics, and human‐machine interaction. However, the advancement of flexible strain sensors is substantially impeded by the intrinsic compromise between sensitivity and the range of detectable signals. Inspired by the multilayer structure of nacre in nature, a carbon nanotubes (CNTs)/graphene (GR)/graphene (GR)/thermoplastic polyurethane (TPU) mat (CGGTM) is prepared by electrospinning and high‐pressure spraying technology. By designing a multilayer structure with mutually non‐interfering conductive networks, the resulting CGGTM possesses a low detection limit (0.05% strain), high sensitivity (gauge factor, GF > 152537), large detection range (up to 364% strain), fast response/recovery time (80 ms/100 ms), and excellent cyclic durability (up to 1000 cycles). Furthermore, the CGGTM also exhibits satisfactory triboelectric performances when assembled into a triboelectric nanogenerator (TENG, 3 × 3 cm2), including high triboelectric output (open‐circuit voltage Voc = 135.4 V, short‐circuit current Isc = 1.25 µA) and power density (88 mW m−2), enabling reliable power supply, self‐powered sensing, and pulse monitoring capability. Finally, CGGTM is successfully applied to the collection of biological signals and multi‐gesture motion recognition assisted by machine learning algorithms, which holds promise for intelligent interaction with gestures in the future. [ABSTRACT FROM AUTHOR]

The floor constitutes one of the largest areas within a building with which users interact most frequently in daily activities. Employing floor sensors is vital for smart‐building digital twins, wherein triboelectric nanogenerators demonstrate wide application potential due to their good performance and self‐powering characteristics. However, their sensing stability, reliability, and multimodality require further enhancement to meet the rapidly evolving demands. Thus, this work introduces a multimodal intelligent flooring system, implementing a 4 × 4 floor array for multimodal information detection (including position, pressure, material, user identity, and activity) and human–machine interactions. The floor unit incorporates a hybrid structure of triboelectric pressure sensors and a top‐surface material sensor, facilitating linear and enhanced sensitivity across a wide pressure range (0–800 N), alongside the material recognition capability. The floor array is implemented by an advanced output‐ratio method with minimalist output channels, which is insensitive to environmental factors such as humidity and temperature. In addition to multimodal sensing, energy harvesting is co‐designed with the pressure sensors for scavenging waste energy to power smart‐building sensor nodes. This developed flooring system enables multimodal sensing, energy harvesting, and smart‐sport interactions in smart buildings, greatly expanding the floor sensing scenarios and applications. [ABSTRACT FROM AUTHOR]

Extracting water from air offers a promising route to address the global challenge of water scarcity. However, bionic engineering surfaces for water harvesting often struggle with efficiently coordinating droplet nucleation and desorption. The recently emerging triboelectric effect at the liquid–solid interface offers a novel approach for developing bionic fog harvesting surfaces. In this study, inspired by Namib Desert beetles and lotus leaves, a biomimetic superhydrophobic surface with nanoscale hydrophilic domains is prepared via interfacial self‐assembly, exhibiting heterogeneous wettability for effective water harvesting. The essence of interfacial self‐assembly lies in the synergy of non‐covalent interaction forces, driving the self‐assembly of nanoparticles into surface micro‐nano hierarchical structures, thereby regulating wettability and increasing potential nucleation sites. Additionally, the triboelectric effect can directly utilize the triboelectric charges to facilitate droplet migration. The triboelectric effect can be generated by flexible mechanical input induced by walking, which enhances interfacial mass transfer, thereby rapidly improving droplet removal and achieving a 39.02% increase in water harvesting efficiency. This study has opened up a new breakthrough for the design of portable and efficient water harvesting systems. [ABSTRACT FROM AUTHOR]

With the development of smart grids, efficient condition monitoring of high voltage transmission system has become crucial, necessitating reliable power supplies for distributed sensors. Traditional energy harvesters often focus on either internal or external sources, limiting overall efficiency. This study introduces a triboelectric‐electromagnetic‐electric field hybrid energy harvester (TEE‐HEH) that synergistically integrates triboelectric nanogenerators (TENGs), electromagnetic generators (EMGs), and electric field energy harvesters (EEHs) to simultaneously capture electric field and wind energy. Electric field energy is harvested via displacement currents between transmission lines and the ground, while TENGs and EMGs efficiently capture low‐ and high‐speed wind energy, respectively, enabling broadband harvesting (2.3–10 m s−1). The synergistic combination of TENG, EMG, and EEH within the TEE‐HEH leads to significantly enhanced energy capture efficiency from multiple sources. At a wind speed of 5 m s−1, a transmission line voltage of 25 kV, and a distance of 1.5 m, the TEE‐HEH achieved peak power outputs of 18.5 mW (TENG), 262 mW (EMG), and 1.85 mW (EEH), demonstrating enhanced energy collection efficiency. An environmental monitoring system has been powered, demonstrating the TEE‐HEH's practicality for dual‐source energy harvesting in smart grid applications. [ABSTRACT FROM AUTHOR]

In the development of smart cities, accurate liquid flow monitoring is essential for the efficient operation of water supply systems. Current flow sensors often face limitations in sensitivity and environmental adaptability, affecting measurement accuracy, and restricting their application in smart city infrastructure. To address these challenges, this study proposes a high‐accuracy flow monitoring method. Specifically, by combining the bionic design with advanced signal processing techniques, the sensitivity and anti‐interference ability are improved, respectively, to enhance the measurement accuracy. Based on this method, a self‐powered flow sensor (SPFS) is developed using noncontact triboelectric nanogenerators (NC‐TENGs) as the sensing unit. The SPFS achieves a sensitivity of 2.07 Hz L−1 min−1 and improves the signal‐to‐noise ratio by more than 13 times over the initial sensing signal. In addition, an intelligent system is developed to accurately measure water resources. The maximum flow rate error rate is less than 0.97% compared to commercial flow sensors. The SPFS demonstrates higher sensitivity and accuracy compared to the existing TENG flow sensors. This study addresses the limitations of existing flow sensors and pioneers a novel solution for enhanced water resource management in smart cities. [ABSTRACT FROM AUTHOR]

Highlights To address the need for efficient, flexible, and wearable power sources for portable electronics, a high performance triboelectric nanogenerator (TENG) was proposed by incorporating vertically‐aligned barium titanate (BaTiO3)/antimony tin oxide (ATO) nanofibers in polydimethylsiloxane (PDMS) negative triboelectric layer, where BaTiO3 served as piezoelectric material, and ATO served as conductive filler. Silver‐coated conductive fabric was used as electrode to ensure integrability and wearability. By strategically coupling the triboelectric effect of PDMS, the piezoelectric effect of BaTiO3 nanofibers, and the charge transfer effect of ATO nanofibers, the TENG exhibited the optimum output voltage and current of approximately 119 V and 28 μA, and power density of 11.74 μW/cm2, respectively. This device demonstrates its potential applications in energy supply by effectively illuminating 174 commercial green LEDs and charging capacitors for powering electronics. Additionally, the successful integration of the TENG into a smart fencing jacket highlights its utility in practical applications. TENGs with vertically‐aligned BaTiO3/ATO composite nanofibers was constructed. The output performance of TENGs were enhanced by coupling triboelectric and piezoelectric effects. Conductive ATO nanofibers were incorporated to enhance charge transfer for performance enhancement. A smart fencing jacket with scoring system was developed using the wearable TENG. [ABSTRACT FROM AUTHOR]

Electrostatic fields are crucial for achieving the highly efficient filtration of airborne pollutants. However, the dissipation of static charges over time, especially under humid conditions, limits their practical application. In this study, we present a self-charging air filter (SAF) powered by a triboelectric nanogenerator (TENG). This SAF is integrated into a commercial mask, termed SAFM, which can effectively capture and degrade airborne pollutants without requiring an external power source. By leveraging the triboelectric effect during breathing, the TENG within the SAFM continuously replenishes static charges, maintaining the triboelectric field. The system employs a cellulose aerogel/Ti3C2Tx composite as the electron donor and an esterified cellulose-based electrospun nanofiber as the electron acceptor. Remarkably, the triboelectric field significantly enhances filtration performance, with the SAF achieving up to 95.7% filtration efficiency for particulate matter as small as 0.3 μm. This work underscores the potential of TENG-powered triboelectric fields in the development of multifunctional, human-machine interactive facemasks. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) are effective in harvesting high‐entropy low‐frequency wave energy, yet traditional TENGs struggle to align with the meter‐scale wavelengths prevalent in marine environments, significantly impairing their wave energy conversion efficiency. Addressing this, the One Meter TENG (OM‐TENG) is introduced, a pioneering advancement in TENG design that extends the shell size to 1 m. This innovation features a novel lantern‐shaped stacked silicon‐manganese steel sheet configuration, optimizing internal space usage, and achieving a single‐cycle transfer charge of 60.82 µC and a friction layer area density of 1.76 cm−1. Furthermore, by integrating a segmented limiter device for rational control of different sliders, effective contact separation among numerous TENG units is realized. Comprehensive evaluations through theoretical analysis, multiphysics field numerical simulations, sensor data analytics, and comparative experimental measurements have unequivocally demonstrated OM‐TENG's superior capability in capturing meter‐scale wave energy under actual environmental conditions, alongside its remarkable anti‐capsize performance. Achieving peak outputs of 584 V and 444 µA, OM‐TENG can power 96 2 W LEDs and drive wireless communication modules, marking a significant step forward in the efficient utilization of wave energy and the design of large‐scale TENGs. [ABSTRACT FROM AUTHOR]

Humidity sensors using triboelectric nanogenerators (TENGs) technology can provide continuous operation without the need for additional batteries. These sensors provide sustainable and self-powered humidity monitoring solutions, that can be utilized in various agriculture platforms and food processing industries. In this work, a sol-gel method is utilized to process the bismuth ferrite (abbreviated as BFO) materials and a simple mould pressing method to obtain freestanding Ethylene-vinyl acetate (abbreviated EVA)-BFO composites. These composites were characterized to shed light upon structural and microstructural properties. The single electrode mode operating TENG was fabricated having 2 cm × 2 cm active area at various wt.% of BFO onto EVA-based composites to compare the electrical response. The 5 wt.% BFO-EVA-based composites/FEP-based TENG generates a voltage and current of 45 V and 800 nA. Further, the TENG device was tested for long-term stability for 400 s, and charging of various capacitors having capacitance values such as 0.1 μF, 1 μF, 4.7 μF, and 10 μF along with 3 times charging/discharging cycles of 0.1 μF capacitor have been demonstrated. The humidity sensing mechanism elucidated which follows the conduction process based on the Grotthuss proton hopping mechanism. The TENG demonstrates a sensitivity of 0.53 V/RH% over the relative humidity range from 25 % to 85 %. The powering of the wristwatch confirms that fabricated TENG can be a reliable power source for future low-power electronics. [ABSTRACT FROM AUTHOR]

Ocean wave energy is one of the most promising green energies in the wild. However, it is still challenging to effectively collect wave energy due to its randomness and irregularity. In this work, a kelp inspired high‐power density triboelectric nanogenerator (K‐TENG) is presented for harvesting wave energy with characteristics in multiple directions. The proposed K‐TENG consists of a series of stacked leaf‐like units. The influence of configuration parameters, including pellet diameters, pellet numbers, unit sizes, oscillation frequency, swing amplitude, and wave directions on output performances of leaf‐like units, are extensively investigated. Experimental data indicates that a single leaf‐like unit can achieve a maximum output voltage of 623.14 V as well as a maximum current of 1.48 µA and realize energy harvesting from different wave directions. A K‐TENG composed of 15 leaf‐like units demonstrates a high‐power density of 18.77 W m−3 at a wave frequency of 2.5 Hz, which successfully powers a digital watch and 414 light‐emitting diodes (LEDs). This work is hoped to provide a simple and reliable route to effectively harvest ocean wave energy. [ABSTRACT FROM AUTHOR]

Harvesting mechanical energy through triboelectric nanogenerators (TENGs) for effectively purifying water, self‐powered wastewater treatment system presents a promising solution to address both energy and environmental crises. However, issues such as side‐discharge and wear, resulting from interfacial charge transfer, seriously hinder the output and durability of TENGs, and then reduce the efficiency of self‐powered wastewater treatment. Here, an interface charge regulation technique is introduced that simultaneously boosts both output performance and durability of TENG, enabling a greater efficiency in self‐powered wastewater treatment. The interface charge regulation method, suppressing side‐discharge around electrodes with an innovative insulator design as well as boosting charge density through secondary collection, fully utilizes surface charges for power output and results in minimum wear by reducing the interface electrostatic force. Surface charge density of 0.8 mC m−2 between the Ethyl tetrafluoro ethylene and copper (µ = 0.35), with a threefold enhancement under ambient conditions, and durability of 500 000 cycles (a 12.5‐fold enhancement) are achieved. Furthermore, the removal efficiency for proposed self‐powered sewage filter system is improved onefold, indicating the potential for sustainable and practical applications. [ABSTRACT FROM AUTHOR]

Currently, enhancing the output power of rotational‐mode triboelectric nanogenerators (TENGs) using various complicated systems is a contentious issue; however, this is a challenging process owing to the inherent characteristics of TENGs, namely, low output currents as opposed to high voltages. Thus, this study proposes a simple and innovative strategy for ultra‐high output peak power generation of TENGs called a self‐boosted rotational electrostatic‐discharge TENG (SRE‐TENG). The SRE‐TENG mechanism is unique as it is based on charge control and boosted discharge design, thereby achieving a remarkable peak power of 1103.8 W, peak power density of 140.6 Kw m−2, low optimum resistance of 100 Ω, and broad peak power generation range of 10 Ω to 1 GΩ. Diligent measurements and analyses of the peak and root‐mean‐square voltage and current outputs of the SRE‐TENG are conducted for various design variables and circuit configurations. The proposed SRE‐TENG mechanism is validated using experimental and multiphysics simulation results. The high‐output performance of the SRE‐TENG is demonstrated via the lighting of 3,000 LEDs and a 60‐W lamp array, continuous driving of a commercial sensor array, and hydrogen/oxygen generation via water electrolysis. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG), as a new technique for energy capture, has unique advantages in harvesting high‐entropy energy. In view of the wind‐induced vibration characteristics of power transmission lines, the symmetric elastic bistable triboelectric nanogenerator (EB‐TENG) is introduced in this work. The core component of the EB‐TENG is the elastic bistable cantilever beam structure, which is designed by introducing an elastic perturbation structure to the conventional cantilever beam. This beam results in several sub‐resonance frequencies in addition to the natural frequencies, which broadens the frequency band of the EB‐TENG. In addition, the EB‐TENG adopts a symmetrical cantilever beam to ensure effective harvesting of vibration energy, even in situations of self‐tilting and external tilting vibration. The experimental outcomes confirm that the EB‐TENG can significantly harvest vibration energy in the 7–60 Hz frequency range and delivers the maximum peak power of 2.846 mW, which meets the major vibration frequency range of power transmission lines under the action of breeze. Finally, self‐powered strategy based on EB‐TENG online monitoring devices (such as tower obstruction lights, temperature and humidity sensors, and line high temperature wireless alarms) is constructed. This work helps promote the application of in‐situ self‐powered monitoring based on TENG in smart transmission lines. [ABSTRACT FROM AUTHOR]

In response to the technical challenge of sustainably powering electrostatic adsorption systems requiring voltages exceeding several thousand volts, a thin film electrostatic adsorption damper (EAD) based on triboelectric high‐voltage is proposed. The core concept of the EAD relies on utilizing the changeable electrostatic force propelled by a rotary freestanding triboelectric nanogenerator (RF‐TENG) to achieve a variable stiffness effect akin to artificial muscle. By adjusting the voltage in accordance with the electrostatic force, the variable stiffness and equivalent damping coefficient can be changed, realizing an electrically controllable damping effect. The modification of dynamic adsorption properties and equivalent damping of the EAD is successfully achieved by investigating a 1D mass‐spring‐EAD vibration system, demonstrating that the damping coefficient can be adjusted from 0.1 to 5 Ns m−1 at different RF‐TENG rotation speeds. Furthermore, the practical applicability of the EAD is validated through the design and testing of a fish‐like scale structure, a joint with variable stiffness, and a heavy‐load lifter. This triboelectric high‐voltage‐based EAD presents a novel approach to sustainable power supply for electrostatic adsorption, which holds significant potential for diverse applications such as advanced cloth defense, artificial muscle technologies, load lifting operations, etc. [ABSTRACT FROM AUTHOR]

The appeal of wearable gas sensors for Internet of Things (IoTs) necessitates flexible sensory units along with sustainable source of energy supply. The key factors required for emergence of these devices are choice of electroactive materials, flexibility, skin‐compatibility, and robustness against harsh environment. Considering this, the multifunctional MXene/CeO2 composites reinforced with electrospun cellulose nanofibers are constructed and investigated for energy conversion, energy storage, and gas sensing applications. Among the synthesized composites, MXene/CeO2 (10 wt%) coated onto cellulose nanofibers outperformed triboelectric nanogenerator (TENG) with open‐circuit voltage of 160 V and supercapacitor (SC) specific capacitance of 388.98 F g−1 and sensing response of 212% toward 10 ppm NH3. The fabricated devices show promising outlooks against practical challenges of influence of humid conditions and different bending states. Lastly, the self‐chargeable device is integrated and the practical implications of charging of SC through TENG and its utilization in sensor powering is demonstrated. The above findings are expected to contribute significantly in envisioning development of wearable health monitors, combining the flexibility features and facilitating autonomous measurements of NH3 pollutant and biomarker. [ABSTRACT FROM AUTHOR]

The performance of triboelectric polymers relies on their molecular structure. Therefore, investigating how to construct high‐performance molecular structures of triboelectric polymers becomes imperative, yet the relationship between microscopic structural parameters and triboelectric performance remains unclear. In this study, the relationship is studied between dihedral angles of adjacent conjugated planes and triboelectric performance. Various polyimide monomers are synthesized to manipulate the conjugated dihedral angles within the molecular chains. Introducing larger dihedral angles in polyimides (PIs) reduces the conjugation between molecular chains, suppressing the formation of charge transfer complexes (CTCs), and widening the energy gap between molecular orbitals. With the increase in dihedral angles, the output performance improved by 100%. The surface charge density of 335 µC·m−2 is achieved through the synergistic effect of the high charge retention capability of the PI film and the high triboelectric properties of the corona‐polarized fluorinated ethylene propylene (FEP). A large dihedral angle can form numerous deep traps and effectively prevent charge escaping while ensuring stable output. This study provides a feasible strategy for investigating the construction of high triboelectric performance molecular structures, enriching the understanding of how molecular structures influence the triboelectric properties of polymer materials and promote high‐performance fluorine‐free and environmentally friendly polymers. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG) for mechanical energy harvesting has been regarded as one of the most prospective energy technologies for the new era. However, inevitable material wear during triboelectrification results in output reduction and even failure of the TENG. In this work, a submillimeter‐scale superlubric TENG (SS‐TENG) is reported that enables ultra‐low friction coefficient (µ) and stable power generation. By using the micro/nano‐processing technology, the interdigital electrodes are embedded into the dielectric layer as a flat surface, on which the highly‐hydrogenated diamond‐like carbon (PLC) is deposited as the triboelectric layer to effectively reduce the friction coefficient. The frictional properties are systematically investigated at different parameters, in which a submillimeter‐scale (130 µm) superlubricity state (µ = 0.0084) is achieved at 4 N, 2 Hz and nitrogen atmosphere. Meanwhile, the SS‐TENG has a maximum power density of 3 mW m−2, which can remain stable at the superlubric condition. This work has first realized the freestanding‐mode superlubric TENG in submillimeter scale and provided a viable strategy for the development of long‐lifetime TENG, which may have great applications in frictional energy recovery from mechanical components, human joint motion, and the natural environment. [ABSTRACT FROM AUTHOR]

The triboelectric nanogenerator (TENG) is a promising technology for self‐powered sensors and vibration‐driven energy harvesting, with its development especially influenced by the characteristics of tribomaterials. However, developing tribopositive materials with a strong cationic effect and high electron‐donating capability remains challenging. In this study, a novel polyethylene oxide@poly(diallyldimethylammonium chloride) (PEO@Poly‐DADMAC) composite nanofiber mat (NFM) is successfully fabricated using the electrospinning technique. It functions as a highly tribopositive material, particularly enhancing the performance of nanofiber‐based TENGs (NF‐TENGs). Through investigation of its physical and triboelectric properties, the study revealed that incorporating cationic Poly‐DADMAC with PEO effectively boosts NF‐TENG output by increasing the dielectric constant (twofold), electron‐donating affinities, and surface charge trapping capability. The fabricated NF‐TENG shows excellent output performance generating 980 V, a maximum power density of 5.6 Wm−2, and an ultrahigh sensitivity of 8.923 V kPa−1 which endows composite reliability for power supply and sensing capability. More importantly, the PEO@Poly‐DADMAC‐based self‐powered motion sensor with an NF‐TENG array is successfully demonstrated in multifunctional applications such as athlete activity tracking, and wireless gaming interface control. This study not only offers new insights into optimizing performance and selecting alternative tribomaterials but also provides valuable guidance for developing high‐output TENGs and highly sensitive self‐powered sensors. [ABSTRACT FROM AUTHOR]

This paper proposes a novel intercalation approach to address the challenges of surface triboelectric charge dissipation and self‐restacking of MXene layers in triboelectric nanogenerators (TENGs). The proposed strategy significantly improves the performance of TENGs, as it prevents the loss of surface charges and enhances the structural stability of MXene. First, the modified silica nanospheres (MSNs) of specific dimensions are synthesized, followed by their intercalation between MXene layers. This not only resolves the restacking issue but also dramatically increases the interlayer distance and MXene's surface area. The MSNs, acting as effective charge storage sites, significantly enhance surface charge density, whereas their high dielectric permittivity generates a synergistic effect that modulates the dielectric constant via polarization. Ultimately, the proposed MSN‐intercalated MXene‐based TENG demonstrates outstanding output performance (output voltage of ≈461 V, output current of ≈19 µA, and maximum peak power density of ≈691.2 µW cm−2) at a 2 wt.% MSN‐intercalated MXene concentration. This study paves a new pathway for the structural design of tribonegative and charge storage layers in TENGs for energy harvesting. [ABSTRACT FROM AUTHOR]

Polydimethylsiloxane (PDMS) is an electron-withdrawing material that is widely used in triboelectric nanogenerators (TENGs). However, PDMS has poor mechanical properties after curing and is easily damaged when subjected to long-term workloads. Thus, the long-term stable operation of TENGs under mechanical deformation cannot be guaranteed. In this work, multiple hydrogen bonds and aromatic disulfide bonds were introduced into PDMS elastomers. These elastomers exhibited high toughness (a tensile strength of 1.91 MPa and an elongation at break of 340%), good recyclability, and room-temperature self-healing properties (healing efficiency of 96.4% in 24 h). Recyclable sandwich-like triboelectric nanogenerators with excellent electrical output performance (13.5 V) and room-temperature self-healing performance (24 h, 98% recovery of self-generating performance) were prepared by utilizing the hydrogen bonding between the PDMS elastomer and MXene. The work reported herein offers theoretical guidance and a compelling strategy for developing high-performance TENG negative friction layers. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) are a viable energy-harvesting technology that can harness kinetic energy from various environmental sources. TENGs primarily utilize linear and rotational motion as their kinetic energy sources. In the contact/separation mode, the primary mode of operation for linear motion, one cycle of AC output is generated with a single push. If the output can be sustained for an extended period from a single push, the potential applications for TENGs would significantly expand. In this study, we propose an innovative Linear-to-Rotary Conversion Triboelectric Nanogenerator (LRC-TENG), which incorporates a gear structure to convert linear motion into rotational motion and employs charge pumping to achieve efficient, prolonged output. The proposed TENG can sustain AC output for 3 s with a single push. This LRC-TENG is particularly well suited for applications such as stairways requiring safety lighting at night. Utilizing the LRC-TENG, when a person steps on a stair, it can illuminate the stairway for 3 s through more than 236 LEDs, ensuring safety during nighttime walking. This solution aids in guaranteeing pedestrian safety at night. [ABSTRACT FROM AUTHOR]

Metal‐organic frameworks (MOFs) are nanomaterials with engineered chemical structures, offering remarkable properties. However, their limited film‐formation capability hinders their integration into triboelectric nanogenerators (TENGs). This study proposes a simple yet effective solution to overcome this challenge by employing electrospinning techniques to integrate the zeolitic imidazolate framework (ZIF‐8) into an easy‐to‐use nanofibrous mat. ZIF‐8 has high surface potential, a unique cubical structure, and an easy fabrication process that makes it an ideal material for TENGs. By incorporating ZIF‐8 into the electrospinning solution, significant improvements are achieved in the electropositivity of the resulting nanofibers. It leads to notable changes in the shape, morphology, and roughness of electrospun fibers, consequently enhancing the overall performance of the TENG. The results indicate that utilizing the ZIF‐based electrospun mat as a tribo‐positive material can increase transferred charges between electrodes by more than 100%. Utilizing the MOF‐based nanofibrous mat, this study also introduces a novel rotary TENG that works based on a mode of TENG operation called rolling mode. The reliable charge generation by the proposed rolling system reveals that this mode of TENG operation could be a superb alternative for traditional TENG modes, like contact/separation or sliding, which cause high levels of mechanical stress due to harsh physical impact or friction. [ABSTRACT FROM AUTHOR]

Highlights: Comprehensively reviewed the progress in research on graphene electrode-based triboelectric nanogenerators (TENGs) from two dimensions, including precision processing methods of graphene electrodes and applications of TENGs. Discussed the various applications of graphene electrode-based TENGs in different scenarios, as well as the ways in which graphene electrodes enhance the performance of TENGs. Offered a prospective discussion on the future development of graphene electrode-based TENGs, with the aim of promoting continuous advancements in this field. With the continuous development of wearable electronics, wireless sensor networks and other micro-electronic devices, there is an increasingly urgent need for miniature, flexible and efficient nanopower generation technology. Triboelectric nanogenerator (TENG) technology can convert small mechanical energy into electricity, which is expected to address this problem. As the core component of TENG, the choice of electrode materials significantly affects its performance. Traditional metal electrode materials often suffer from problems such as durability, which limits the further application of TENG. Graphene, as a novel electrode material, shows excellent prospects for application in TENG owing to its unique structure and excellent electrical properties. This review systematically summarizes the recent research progress and application prospects of TENGs based on graphene electrodes. Various precision processing methods of graphene electrodes are introduced, and the applications of graphene electrode-based TENGs in various scenarios as well as the enhancement of graphene electrodes for TENG performance are discussed. In addition, the future development of graphene electrode-based TENGs is also prospectively discussed, aiming to promote the continuous advancement of graphene electrode-based TENGs. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs) have emerged as promising materials for triboelectric nanogenerators (TENGs), but the effects of ligand choice on triboelectric charge remain underexplored. Hence, this paper demonstrates the effect of single, binary, and ternary ligands on TENG performance of cobalt/cerium‐based (Co─Ce) bimetallic MOFs utilizing 2‐methylimidazole (2Melm), terephthalic acid (BDC), and benzene tricarboxylic acid (BTC) as ligands. The detailed structural characterization revealed that varying ligand chemistries led to distinct MOF features affecting TENG performance. Single ligand bimetallic MOFs (designated as CoCe‐2MeIm, CoCe‐BDC, CoCe‐BTC) has lower performance than binary ligand (designated as CoCe‐2MeIm‐BDC, CoCe‐2MeIm‐BTC, CoCe‐BDC‐BTC) and ternary ligand MOFs (designated as CoCe‐2MeIm‐BDC‐BTC). Among all, the binary ligand MOF, CoCe‐2MeIm‐BTC, shows the best results (598 V, 26.7 µA) due to the combined effect of imidazole ring and (─COO─) groups. This is attributed to lone pairs on nitrogen atoms and a delocalized π‐electron system in imidazole system in this material. CoCe‐BTC has the lowest results (31 V, 3.2 µA) due to the bulkier nature of the electron‐withdrawing (─COO─) groups and their impact on the π‐electron system of the benzene ring. This study showcases the potential of ligand chemistry manipulation to control triboelectric charge and thereby enhance MOF‐based TENG performance. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA), a versatile polymer, is extensively used across many industries, such as chemicals, food, healthcare, textiles, and packaging. However, research on applying PVA to triboelectric nanogenerators (TENGs) remains limited. Consequently, we chose PVA as the primary material to explore its contact electrification mechanisms at the molecular level, alongside materials like Polyethylene (PE), Polyvinylidene fluoride (PVDF), and Polytetrafluoroethylene (PTFE). Our findings show that PVA has the highest band gap, with the smallest band gap occurring between the HOMO of PVA and the LUMO of PTFE. During molecular contact, electron transfer primarily occurs in the outermost layers of the molecules, influenced by the functional groups of the polymers. The presence of fluorine atoms enhances the electron transfer between PVA and PTFE to maximum levels. Experimental validation confirmed that PVA and PTFE contact yields the highest triboelectric performance: VOC of 128 V, ISC of 2.83 µA, QSC of 82 nC, and an output power of 384 µW. Moreover, P-TENG, made of PVA and PTFE, was successfully applied in self-powered smart devices and monitored human respiration and bodily movements effectively. These findings offer valuable insights into using PVA in triboelectric nanogenerator technologies. [ABSTRACT FROM AUTHOR]

Dynamic loads are inevitably generated during the operation of rotating machinery. In situ monitoring the dynamic loads is of great significance for assessing shafting health. Triboelectric nanogenerator (TENG) is sensitive to motion but not suitable for load monitoring, while piezoelectric nanogenerator (PENG) is just the opposite. Therefore, the combination of the two can complement each other. From this, a dynamic load monitoring smart bearing (DLMSB) integrated with TENG and PENG is proposed. The specially designed TENG can produce an “M‐waveform”, which can be used to extract rotation frequency and distinguish the quadrant of the rotor. Meanwhile, applying PENG to capture the load condition of the bearing, and referring to the main frequency of M‐waveform, it is convenient to obtain the dynamic loads of shafting. Furthermore, a real‐time monitoring system is developed, which can realize not only real‐time monitoring of the rotation speed and dynamic loads magnitude but also the quadrant discriminating of dynamic loads. The results have shown that the monitoring error for dynamic loads is 3 N or 5.5%, and the accuracy rate for determining the quadrant of the dynamic loads can reach 93%. This study provides a novel approach for the in situ monitoring of mechanical operating status via nanogenerators. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerators (TENGs) have become reliable green energy harvesters by converting biomechanical motions into electricity. However, the inevitable charge leakage and poor electric field (EF) of conventional TENG result in inferior tribo‐charge density on the active layer. In this paper, TiO2‐MXene incorporated polystyrene (PS) nanofiber membrane (PTMx NFM) charge trapping interlayer is introduced into single electrode mode TENG (S‐TENG) to prevent electron loss at the electrode interface. Surprisingly, this charge‐trapping mechanism augments the surface charge density and electric output performance of TENGs. Polyvinylidene difluoride (PVDF) mixed polyurethane (PU) NFM is used as tribo‐active layer, which improves the crystallinity and mechanical property of PVDF to prevent delamination during long cycle tests. Herein, the effect of this double‐layer capacitive model is explained experimentally and theoretically. With optimization of the PTMx interlayer thickness, S‐TENG exhibits a maximum open‐circuit voltage of (280 V), short‐circuit current of (20 µA) transfer charge of (120 nC), and power density of (25.2 µW cm−2). Then, this energy is utilized to charge electrical appliances. In addition, the influence of AC/DC EF simulation in wound healing management (vitro L929 cell migration, vivo tissue regeneration) is also investigated by changing the polarity of trans‐epithelial potential (TEP) distribution in the wounded area. [ABSTRACT FROM AUTHOR]

The long‐term durability of triboelectric nanogenerators (TENGs) remains a main challenge for practical applications because of inevitable material abrasion and wear, especially for sliding TENGs. Herein, an inorganic triboelectric pair composed of diamond‐like carbon (DLC) and glass with excellent durability and triboelectric output for sliding‐mode TENGs is proposed. This triboelectric pair possesses a low coefficient of friction and little abrasion and accordingly excellent durability (>500 000 cycles). Moreover, compared with the traditional copper‐polytetrafluoroethylene (Cu‐PTFE) TENG with maximum transferred charges of 50 nC, those of the DLC‐glass TENG reaches 141 nC. Due to the low‐friction and high hardness of the triboelectric pair, the output quickly recovers after simply cleaning wear debris. The DLC‐glass TENG demonstrates an output power density of 530 mW m−2 and a fourfold faster capacitor charging speed than the Cu‐PTFE TENG. Compared to the reported durable TENGs via structure optimization and interface lubrication, the DLC‐glass TENG shows higher outputs and simpler structure. This DLC‐glass pair structure is also introduced into a spherical TENG for blue energy harvesting with excellent durability. The inorganic triboelectric pair with excellent mechanical durability and electrical performance proposed in this work shows huge prospects for practical applications of TENGs. [ABSTRACT FROM AUTHOR]

Herein, 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. [ABSTRACT FROM AUTHOR]

This study presents a freestanding sliding triboelectric nanogenerator (FS‐TENG) designed for low‐frequency motions (below 2 Hz). However, for practical applications, an efficient power management strategy is required to handle the harmonic outputs of the FS‐TENG. The high‐frequency signal is not sustainable for powering low‐power electronic applications. To address the issue, a novel direct current power supply circuit (DPS) is proposed that utilizes a double charge circuit (DCC) and a comb filtering circuit (CFC) to efficiently harness harmonic sources from the FS‐TENG. The direct power supply (DPS) outperforms traditional converters by reducing the impedance of the FS‐TENG and collecting the target harmonic sources, which facilitates a continuous power supply to the load. The results demonstrate that the DPS is capable of providing a continuous DC voltage of 2.2 V to a 10 MΩ load with minimal ripple (0.039%) at a low operating frequency of 0.625 Hz. Additionally, the practical application of a self‐powered temperature sensor is demonstrated to highlight the potential of FS‐TENG and DPS for low‐frequency energy harvesting solutions in real‐world scenarios. [ABSTRACT FROM AUTHOR]