Search

Power management is an efficacious route to promote the development of triboelectric nanogenerators (TENGs), in which the buck switch for efficient energy extraction has always been a challenge. Here, we propose a three-port cantilever buck switch which can autonomously release energy from the TENG in maximum by the generated electrostatic field of the TENG. The influence of closing voltage of the buck switch on different structure parameters has been thoroughly investigated. The U-Q curve indicates that the optimal energy extraction can reach 90.86%, and the matched impedance of the TENG is reduced from 60 MΩ to 470 kΩ. Compared to the output power at matched impedance, the average power managed by this three-port cantilever buck switch is increased by 1.554 times, which can power the Bluetooth device, electronic watch, calculator and thermo-meter. This work has realized ultra-efficient power management of TENG by leveraging an autonomous cantilever buck switch, which can contribute to the efficient utilization of micromechanical energy. • A three-port cantilever buck switch controlled by the electrostatic field of the TENG for its power management is pioneered. • A detailed analysis of the force-electricity conversion process has been conducted. • U-Q curve and P-R curve has been linked to characterize the output efficiency for the first time. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG) is a new energy technology based on interface contact electrification, in which the surface micro/nano-structures of triboelectric layers have great impacts on output performances. Here, we propose micro/nano-structures-enhanced triboelectric nanogenerators by femtosecond laser direct writing on both triboelectric layers. With a laser scanning ablation technology, the micro/nano dual-scale structures in stripes and cones are fabricated on Cu film surfaces, respectively. While the micro-bowls structure in different sizes are fabricated on polydimethylsiloxane (PDMS) surfaces by single pulse irradiation. Based on these prepared triboelectric layers, several kinds of TENGs in contact-separation mode are systematically characterized, in which the TENG with micro/nano-cones structure on Cu surface and micro-bowls structure on PDMS surface has the optimal performances and achieves about 21 times enhancement in power density. This work provides an effective femtosecond laser direct writing process for fabricating micro/nano-structures on both triboelectric layers and enhancing the output performances of TENG, which would greatly promote the practicality of TENG in mass manufacturing and micro-energy utilization. Image 1 • The TENG with double triboelectric layers processed by femtosecond laser direct writing is investigated. • The different micro/nano structure are fabricated on the Cu and PDMS films with femtosecond laser direct writing. • The output power of TENG can be increased by 21 times by femtosecond laser direct writing method. • The TENG is demonstrated as a power source for continuously driving electronic devices and charging an energy storage unit. [ABSTRACT FROM AUTHOR]

Harvesting ocean wave energy is a killer application of triboelectric nanogenerator (TENG) for advantages in simple mechanism, high power density and high efficiency at low frequency. Here we report a self-powered intelligent buoy system (SIBS), in which a high-output multilayered TENG is used for water wave energy harvesting. With a power management module, the output voltage can be converted and regulated as a steady DC voltage of 2.5 V for the operations of a microprogrammed control unit (MCU), several micro sensors and a transmitter. With the intelligent monitoring mechanism of the MCU, the harvested energy can be deployed for each sensor with different priority and data transmission cycle, and the SIBS can be at standby and active status by itself at different energy levels. At a wave frequency of 2 Hz, the SIBS can provide an average output power density of 13.2 mW/m2 and realize sustainable and autonomous wireless sensing for acceleration, magnetic intensity and temperature in range of 15 m, with amount of 19 bytes every 30 s. The SIBS has first demonstrated a complete TENG-based micro-energy solution for self-powered intelligent system, including energy harvesting, management, deployment and utilization, with an unattended manner and infinite lifetime. As a significant milestone for the TENG, this work has provided a universal platform for self-powered wireless sensor network nodes and exhibited broad prospects in internet of things, big data, artificial intelligence and blue energy. We propose a self-powered intelligent buoy system (SIBS), including a high-output multilayered TENG for harvesting water wave energy, which can be used for sustainable and autonomous wireless sensing and data transmission. Image 1 • A self-powered intelligent buoy system (SIBS) is proposed, in which a high-output multilayered TENG is used for water wave energy harvesting. • With a power management module, the output voltage can be converted and regulated as a steady DC voltage of 2.5 V for the operations of a microprogrammed control unit (MCU), several micro sensors and a transmitter. • With the intelligent monitoring mechanism of the MCU, the harvested energy can be deployed for each sensor with different priority and data transmission cycle, and the SIBS can be at standby and active status by itself at different energy levels. • This work has provided a universal platform for TENG-based self-powered wireless sensor network nodes and exhibited broad prospects in internet of things, big data, artificial intelligence and blue energy. [ABSTRACT FROM AUTHOR]

Triboelectric nanogenerator (TENG) is a new energy technology that is as important as traditional electromagnetic generator (EMG) for converting mechanical energy into electricity, which shows great advantages of simple structure, high power density and low-frequency. Here, the effects of motion amplitude for both generators are first taken into consideration. Our result demonstrates that the TENG has a much better performance than that of the EMG at small amplitude. Under fixed operation frequency, the maximum output power of the TENG rapidly grows to saturation with the increase of the amplitude, while that of the EMG grows slowly and gradually. This contrastive characteristic is verified at different frequencies, which has demonstrated that the TENG has dominant scope over the EMG, in not only low-frequency but also small-amplitude. Moreover, electronics powered by the TENG in small-amplitude has been exhibited and an overall comparison of the TENG and EMG is summarized. Beyond low-frequency, this work has verified the small-amplitude is also a remarkable merit of the TENG for harvesting micro-mechanical energy, which has guided the development prospects of TENG as a foundation of the energy for the new era for internet of things, wearable electronics, robotics and artificial intelligence. Image 1 • This is the first paper to compare the effects of motion amplitude for EMG and TENG, which demonstrates that the TENG has a much better performance than that of the EMG at small amplitude. • This contrastive characteristic is verified at different frequencies, which has demonstrated that the TENG has dominant scope over the EMG, in not only low-frequency but also small-amplitude. • An overall comparison of the TENG and EMG is summarized, in which the small-amplitude is also a remarkable merit of the TENG as a foundation of the energy for the new era. [ABSTRACT FROM AUTHOR]

Abstract Water wave energy is regarded as one of the most prospective renewable energy sources, while most of it has not been utilized for numerous technology defects. As a new energy technology, triboelectric nanogenerator (TENG) has been widely utilized for low frequency and random mechanical energy harvesting, which is very suitable for scavenging water wave energy. In this paper, we present a torus structured triboelectric nanogenerator (TS-TENG) which consists of an inner ball and a torus shell. Triggered by water waves, the ball revolves in the torus shell for triboelectric power generation, and the TS-TENG can harvest random wave energy from all directions. Moreover, to scavenge large-scale water wave energy, the TS-TENG array is fabricated and presented as a power source for persistently powering electronic devices and charging a battery or capacitor. With an agitation frequency of 2 Hz and an oscillation angle of 5°, the TS-TENG is expected to give a maximum peak power density of 0.21 W/m2. Take advantage of low-cost, environment-friendly and easy- implement, the development of the TS-TENG is of great significance for harvesting large-scale ocean wave energy and other potential applications in blue energy. Graphical abstract Triggered by water waves, the inner ball revolves in the torus shell for triboelectric power generation, and the TS-TENG can harvest random wave energy from all directions. Moreover, to scavenge large-scale water wave energy, the TS-TENG array is fabricated and presented as a power source for persistently powering electronic devices and charging a battery or capacitor. fx1 Highlights • A torus structured triboelectric nanogenerator (TS-TENG) which encloses an inner ball inside a torus shell is investigated. • Triggered by water waves, the ball revolves in the torus shell for triboelectric power generation, and the TS-TENG can harvest random wave energy from all directions. • The TS-TENG array is fabricated and demonstrated as a power source for continuously driving electronic devices and charging an energy storage unit. • With an agitations frequency of 2 Hz and an oscillation angle of 5°, the TS-TENG is expected to give a maximum peak power density of 0.21 W/m2. [ABSTRACT FROM AUTHOR]

Effective power management has always been the difficulty and bottleneck for practicability of triboelectric nanogenerator (TENG). Here we propose a universal power management strategy for TENG by maximizing energy transfer, direct current (DC) buck conversion, and self-management mechanism. With the implemented power management module (PMM), about 85% energy can be autonomously released from the TENG and output as a steady and continuous DC voltage on the load resistance. The DC component and ripple have been systematically investigated with different circuit parameters. At a low frequency of 1 Hz with the PMM, the matched impedance of the TENG has been converted from 35 MΩ to 1 MΩ at 80% efficiency, and the stored energy has been dramatically improved in charging a capacitor. The universality of this strategy has been greatly demonstrated by various TENGs with the PMM for harvesting human kinetic and environmental mechanical energy. The universal power management strategy for TENG is promising for a complete micro-energy solution in powering wearable electronics and industrial wireless networks. With the new coupling mode of triboelectricity and semiconductor in the PMM, the tribotronics has been extended and a new branch of power-tribotronics is proposed for manageable triboelectric power by electronics. [ABSTRACT FROM AUTHOR]

Overspeed information monitoring and collecting becomes increasingly important with the rapid development of intelligent transportation, but current overspeed monitoring technologies are constrained by traditional power-supply for large-scale use. Herein, we proposed a self-powered overspeed wake-up alarm system (SOWAS) based on triboelectric nanogenerators. The SOWAS consists of an energy harvesting triboelectric nanogenerator (E-TENG), an energy management module (EMM), an overspeed sensing triboelectric nanogenerator (S-TENG), a power-switch module (PSM) and a wireless transceiver module (WTM). The E-TENG and EMM are used for mechanical energy harvesting, management, and powering for the SOWAS, while the S-TENG, PSM and WTM are employed for active overspeed monitoring and alarm signals transmitting. When the vehicle speed exceeds the setting threshold, the PSM will be activated, and the WTM will send alarm signals with the harvested energy. The response characteristics dependence of the SOWAS on various working parameters were investigated in detail. The developed SOWAS could work sustainably in unattended traffic environment without external power supply for autonomous overspeed monitoring and alarming. Meanwhile, intelligent monitoring of overspeed and improved energy utilization were achieved. This work has enormous potentials and promising prospects for TENG in intelligent transportation, Internet of Vehicles and autonomous driving. [Display omitted] • A self-powered overspeed wake-up alarm system (SOWAS) based on TENGs is developed. • The SOWAS enables sustainable self-powered overspeed monitoring and alarm by harvesting the mechanical energy from traffic system. • Intelligent overspeed monitoring is achieved by the designed wake-up circuit and the efficient use of energy. [ABSTRACT FROM AUTHOR]

Obtaining a wear-resistant, high-output, flexible direct current (DC) friction energy harvester is quite important for implementing self-powered portable electronic devices and Internet of Things (IoT). In this work, a direct current flexible textile organic tribovoltaic nanogenerator (FT-OTG) is reported, which is consisted of blended film of 11.11% poly(3,4-ethylenedioxythiophene): poly(styrene sulfonate) (PEDOT: PSS) and 88.89% polyvinyl alcohol (PVA), a hydrophilic conductive ink, a hydrophobic conductive textile and Al slider. The working mechanism of OTG is that after absorbing friction energy, abound electron-hole pairs are excited at the metal-semiconductor interface. These carriers move directionally under the joint drive of electrostatic field and the built-in electric field to form a current. After PVA doping, the output performance of DC-OTG, including open-circuit voltage and short-circuit current, is improved 5.6 times and 4.2 times, respectively. Furthermore, the mechanical properties of blended film, such as wear resistance, elongation and tensile strength, are improved, among which elongation at break is increased by 8 times and tensile strength increased by 3.2 times. By simplify series connecting, 3 FT-OTGs can constantly power portable electronics, like electronic watch, thermometer and calculator, respectively. This work provides an effective way for simultaneously enhanced output performance and mechanical properties of FT-OTG, which is expected to be a robust way for harvesting friction energy for self-powered electronics device and IoT sensors. [Display omitted] • A direct current FT-OTG is reported. By simplify series connecting, 3 FT-OTGs can constantly power portable electronics. • The enhancement mechanism is the E CE and E built-in field jointly promote the directional motion of charge carriers. • After PVA doping, output performance and mechanical performance have been significantly improved. [ABSTRACT FROM AUTHOR]

Electrostatic manipulation of particles or droplets has raised huge interests across many fields including biomedical analysis, microchemistry and microfabrication/patterning, because of its merits of simple configuration and easy operation. However, traditionally applied bulky high voltage sources for electrostatic manipulation not only have potential safety risk to the operator and the devices, but also limit the portability. Here, we proposed an electrostatic microparticle manipulation system (EMMS) based on a triboelectric nanogenerator (TENG). Inspired from the pollen collection principle of honeybees, the EMMS featured a simple pin-to-plate electrodes system, which was electrostatically powered by the high voltage of the TENG. Different manipulation modes, including contact manipulation and noncontact manipulation were systematically studied. With a sliding displacement of 5 cm, the TENG delivered an output voltage of ± 3.2 kV, which could manipulate dielectric microparticles with weights of 1.7 mg, 0.9 mg and 13.3 mg at contact manipulation mode, noncontact manipulation (vertical lift) and noncontact manipulation (parallel move) mode, respectively. Manipulation mechanisms for both dielectric and conductive microparticles under different configurations of the pin-to-plate electrodes system were investigated. Finally, potential applications including micropatterning, dust remove and drug release/microchemistry were demonstrated to show the great prospects of the proposed TENG-based EMMS. [Display omitted] • A honeybee-inspired electrostatic microparticle manipulation system was proposed based on a triboelectric nanogenerator. • Different manipulation modes, including contact manipulation and noncontact manipulation were systematically studied. • Manipulation mechanisms under different configurations of the pin-to-plate electrode system were investigated. • Potential applications including micropatterning, dust remove and drug release/microchemistry were demonstrated. [ABSTRACT FROM AUTHOR]

Vibrational triboelectric nanogenerators (V-TENG) can be used to harvest broadband vibration energy due to the nonlinear impact force induced by a stopper. However, V-TENGs with a single stopper have limited bandwidth and surface charge density, which has limited their application in wideband vibration energy harvesting. Herein, a V-TENG with two stoppers and a charge pumping effect is proposed for frequency band broadening and charge density enhancement. The theoretical analysis and experimental validation have indicated the V-TENG with two stoppers could improve the bandwidth by 75% compared with one stopper at a gap distance of 0.5 mm. Moreover, a charge pump can be constructed with two output channels, which has improved surface charge density by about 14 times. With the frequency varying from 18 to 38 Hz, the V-TENG can continually power 400 LEDs and charge a commercial capacitor quickly. This work has shown an encouraging method for enhancing the performance of V-TENGs, which also has great prospects in harvesting wideband vibration energy from machines, cars, ships, and human motions for self-powered electronics. The frequency band broadening mechanism and charge density enhancement technique of the vibrational TENG (V-TENG) were systematically elaborated. The introduction of double-sided stoppers strengthens the nonlinear characteristics of the V-TENG and broadens the frequency band. Furthermore, a high-performance V-TENG based on charge pump (CPV-TENG) is constructed according to the two output channels of the V-TENG. [Display omitted] • Research on the frequency band characteristics of a V-TENG based on two stoppers by theoretical analysis and simulation. • Demonstration of the frequency band broadening features of V-TENG under different conditions by experimental exploration. • A high-performance CPV-TENG based on the charge pump effects is constructed according to two output channels of V-TENG. [ABSTRACT FROM AUTHOR]

The textile-based triboelectric nanogenerator (tTENG) is one of the most promising energy harvesting devices for realizing self-powered smart textiles and wearable electronics. Herein, we report a scalable machine-knitting fabrication of stretchable, washable and breathable tTENGs for harvesting human motion energies. A plating stitch technique is employed to fabricate tTENGs using various common yarn materials and working in different modes (coplanar sliding mode and contact-separation mode). The tTENG can output voltage up to 232 V and power density up to 66.13 mW/m2. Furthermore, it can constantly power different wearable electronics by integrating with a small-size power management module, which converts the irregular AC output to a stable DC output and improves the energy utilization of tTENG. The stretchability, washability and air permeability of the tTENG are also demonstrated. These findings provide a practically viable textile-based power source that holds great promise in future self-powered wearable electronics and smart textiles. [Display omitted] A stretchable, washable and breathable textile-based triboelectric nanogenerator is fabricated by a scalable knitting method for harvesting human motion energies, which can provide continuous power to different small electronics with the aid of a small-sized power management module. This work presents a feasible and practical power alternative for wearable electronics and E-textiles. • Scalable fabrication of stretchable, washable and breathable textile triboelectric nanogenerators (tTENG) is demonstrated. • The tTENG generates high electrical outputs by harvesting human motion energies. • The tTENG can constantly power different wearable electronics with the aid of a small-size power management module. [ABSTRACT FROM AUTHOR]

Replacing the diseased joints with artificial prostheses has long been a common medical mean to alleviate pain or disability, in which the wear debris-induced aseptic loosening is the main mechanism for failure of artificial joint replacement. Timely and in situ detection of the wear debris is necessary to prevent further deterioration of the joint, and provides a basis for the lifetime diagnosis of artificial joint. Here, a self-powered sensor based on triboelectric nanogenerator (TENG) was developed for detecting wear debris generated in artificial joint. The TENG with polyethylene film and steel ball was designed into artificial joint configuration and fabricated by thermo-compression, which could in-situ detect the production of wear debris. Furthermore, the dependence of electrical output signals on the amount and size of the debris was investigated, which demonstrated obvious decrease in voltage with the increase in the amount and size of the particles. Finally, the fabricated sensor was tested in joint wear simulator, which achieved the real-time wear debris monitoring. This work expands the application of TENG in artificial joint wear detection, which is expected to promote the development of biomedical sensor and intelligent healthcare. [Display omitted] • The TENG-based sensor is fabricated in artificial joint by thermo-compression. • The self-powered sensor can in-situ detect the amount and size of wear debris. • The real-time wear debris monitoring is achieved in joint wear simulator. [ABSTRACT FROM AUTHOR]

As the technology of the Internet of Things (IoT) develops, trillions of wireless nodes need to be powered. It's of significant importance to design self-powered systems by utilizing tirboelectric nanogenerators (TENG) to harness energy from environment. In this paper, a wind-driven self-powered wireless environmental sensing system is presented. A TENG working in the contact-separation mode with high output performance is designed and optimized to convert wind energy into electricity. Nine TENG units are then assembled into a 3D printed shell and demonstrated as a power source for two environmental monitoring systems. At a wind speed of 4.5 m/s, a Carbon monoxide (CO) monitor works sustainably and sends out a signal from 1.5 km away every 18 min, by using the radio transmission with 433 MHz ultrahigh frequency (Sub-1G). Another temperature and humidity hybrid sensor can send out the monitoring data every 9 min through Bluetooth (2.4 GHz) in a range of 50 m. Above all, this wind-driven self-powered system constructs a platform, which can be widely used in any other wireless remote environmental sensing scene, requiring sustainability and free of maintenance. Self-powered wireless environmental sensors (SWES) combined with wind-TENG is designed to address the problem of energy consumption, automatic detection and environmental protection. By collecting wind energy, the SWES can transmit sensing data with a distance reaching up to 1.5 km in 18 min, which will affect the development of environmental detection enormously on Internet of Things area. Image 1 • Different TENG structure's parameters are optimized achieving highest output performance. • The self-powered sensor can transmit environmental data within 50 m in 9 min. • The self-powered sensor can transmit environmental data away from 1.5 km in 18 min. • The robust system can adapt complicated environment. [ABSTRACT FROM AUTHOR]

Smart sensor is the foundation and core of intelligent manufacturing, which is developing for miniaturization, integration and self-powering. Here, we report an active sensor array based on single-electrode triboelectric nanogenerators (TENGs) for dynamic wear monitoring and positioning. The sensor unit is fabricated by embedding the electrode into the core-shell composite with polytetrafluoroethylene (PTFE) as the core and polymethylmethacrylate (PMMA) as the shell. The working mechanism and performances of the sensor unit with different parameters including the thickness of PTFE@PMMA layer, reciprocating frequency, sliding displacement, electrode width and the diameter of copper bar are systematically investigated and discussed. By integrating into the sensor array, the dynamic wear monitoring and positioning have been realized, which can be used to detect the wear states of multiple regions in the sliding bearing system. This work has extended the application of the TENGs to determine the wear states of polymer interface and may promote the great development of intelligent bearing. Image 1 • By embedding the electrode into the core-shell composite (PTFE@PMMA), the sensor unit is fabricated. • A planar sensor array based on single-electrode triboelectric nanogenerators for wear monitoring and positioning is realized. • Integrating into the sensor array, it is used to detect the wear states of multiple regions in the sliding bearing system. [ABSTRACT FROM AUTHOR]

A compact, springless, easy-to-process kirigami-inspired TENG (KI-TENG) is developed. The frequency responses of the KI-TENG under the influence of mass, acceleration, and initial distance are investigated in detail to optimize its structural design. Moreover, the TENG coupled with the kirigami structure could collect ultra-wide-band vibration energy and as a sensor measuring acceleration. [Display omitted] • A compact and springless kirigami-inspired TENG (KI-TENG) is developed. • The frequency response characteristics of the KI-TENG are investigated. • The KI-TENG can harvest ultra-wide-band vibration energy from 2 to 49 Hz. • The output of the KI-TENG at different vibration tilt angles is explored. • The KI-TENG can effectively monitor acceleration changes from 1 to 9 m/s2. Triboelectric Nanogenerators (TENGs) based on spring-assisted structures play a central role in scavenging vibrational energy that is widely available in the natural environment. However, they suffer from difficulties in adjusting the stiffness and bonding the springs to the triboelectric layer. Here, a kirigami-inspired TENG (KI-TENG) with a kirigami structure is demonstrated, which can be used as an ultra-wide-band vibrational energy harvester and self-powered acceleration sensor. The triboelectric layer of the KI-TENG can be easily processed into the kirigami structure with one or two-degree-of-freedom by laser cutting technology. The frequency responses of the KI-TENG under the influence of mass, acceleration, and initial distance are investigated in detail to optimize the structural design. With optimized structural parameters, the KI-TENG can not only harvest broadband vibration energy from 2 to 49 Hz in vertical vibration state but also obtain high output performance over a wide frequency range in horizontal vibration state. Moreover, the KI-TENG can be used as a sensor measuring acceleration from 1 to 9 m/s2. This work demonstrates a compact TENG coupled with the kirigami structure for energy harvesting and active sensing, which has great prospects in intelligent plants, artificial intelligence, and the internet age. [ABSTRACT FROM AUTHOR]

The use of renewable resources to generate energy is one of the most important policy goals in the energy sector. One method to use renewable resources is to apply integrated systems. In this study, an optimal multi-objective integrated system has been applied to power generation. The proposed system includes wind turbines, hydroelectric power plants, and photovoltaic systems. To achieve maximum power generation with minimum fluctuations, a Developed Owl search algorithm (DOSA) with three pareto front solutions has been used. Also, the efficiency of the integrated system in different climate conditions is evaluated. The results of the pareto front show that the developed owl search algorithm is the closest algorithm to the pareto front. Therefore, it is the most accurate to improve the overall multi-objective integrated system. Among pareto front solutions, the second solution provides acceptable results for increasing power generation and reduction of fluctuations. Also, the results of the evaluation of the efficient integrated system in different climate conditions show that in wet conditions when solar radiation and wind are reduced, hydropower causes current to continue in the system by generating electricity and compensating for wind and PV energy loss. • A wind-photovoltaic-hydropower hybrid system has been used. • The Developed Owl search algorithm is used to improve efficiency of the system. • Three climatic conditions are used to analyze the efficiency of the hybrid system. • The system can continue to generate power well in different climate. [ABSTRACT FROM AUTHOR]