A Highly Efficient and Durable Kirigami Triboelectric Nanogenerator for Rotational Energy Harvesting

While sliding-mode triboelectric nanogenerators (S-TENGs) have been considered as one of the most promising devices for rotational energy harvesting, their inherently poor durability has been a serious bottleneck for applications. Herein, we report a three-dimensional kirigami TENG as a highly efficient and durable rotational energy harvesting device. The kirigami TENG consisted of cube-shaped paper, aluminum (Al) foil electrode and polytetrafluoroethylene (PTFE) polymer film, and converted rotational motion into multiple folding-unfolding vibrations. The rotation-folding (R-F) kirigami TENG generated an open-circuit voltage of 31 V, a short-circuit current of 0.67 μA and an instantaneous power (power density) of 1.2 μW (0.13 μW/cm2) at 200 rpm, which was sufficient to turn on 25 light-emitting diodes and a thermo-hygrometer. The triboelectric outputs of the R-F kirigami TENG were only slightly decreased even after 288,000 continuous rotations, i.e., the output remained at 86% of its initial value. This work demonstrates that an R-F kirigami TENG could be a plausible candidate to efficiently harvest various forms of rotational energy with a long-term durability.

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Omni-directional wind-driven triboelectric nanogenerator with cross-shaped dielectric film

Nano Convergence ◽

10.1186/s40580-021-00276-5 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Yoseop Shin ◽

Sungjun Cho ◽

Sejin Han ◽

Gun Young Jung

Keyword(s):

Wind Energy ◽

Dielectric Film ◽

Mechanical Energy ◽

Short Circuit ◽

Short Circuit Current ◽

Open Circuit ◽

Dielectric Films ◽

Triboelectric Nanogenerator ◽

External Power ◽

Triboelectric Nanogenerators

AbstractTriboelectric nanogenerators (TENGs) are actively being researched and developed to become a new external power unit for various electronics and applications. Wind is proposed as a mechanical energy source to flutter the dielectric film in wind-driven TENGs as it is clean, abundant, ubiquitous, and sustainable. Herein, we propose a TENG structure with dielectric films bent in four directions to collect the wind energy supply from all directions, unlike the conventional wind-driven TENGs which can only harvest the wind energy from one direction. Aluminum (Al) layer was intercalated within the dielectric film to improve electrostatic induction, resulting in improved triboelectric performances. Maximum open-circuit voltage (Voc) of 233 V, short-circuit current (Isc) of 348 µA, and output power density of 46.1 W m− 2 at an external load of 1 MΩ under a wind speed of 9 m s− 1 were revealed, and it faithfully lit “LED” characters composed of 25 LEDs.

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Flexible Ag Microparticle/MXene-Based Film for Energy Harvesting

Nano-Micro Letters ◽

10.1007/s40820-021-00729-w ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Yunpeng Jia ◽

Yamin Pan ◽

Chunfeng Wang ◽

Chuntai Liu ◽

Changyu Shen ◽

...

Keyword(s):

Energy Harvesting ◽

Open Circuit Voltage ◽

Short Circuit ◽

Short Circuit Current ◽

Waterborne Polyurethane ◽

Open Circuit ◽

Heating Performance ◽

Flexible Films ◽

Different Types ◽

Triboelectric Nanogenerators

AbstractUltra-thin flexible films have attracted wide attention because of their excellent ductility and potential versatility. In particular, the energy-harvesting films (EHFs) have become a research hotspot because of the indispensability of power source in various devices. However, the design and fabrication of such films that can capture or transform different types of energy from environments for multiple usages remains a challenge. Herein, the multifunctional flexible EHFs with effective electro-/photo-thermal abilities are proposed by successive spraying Ag microparticles and MXene suspension between on waterborne polyurethane films, supplemented by a hot-pressing. The optimal coherent film exhibits a high electrical conductivity (1.17×104 S m−1), excellent Joule heating performance (121.3 °C) at 2 V, and outstanding photo-thermal performance (66.2 °C within 70 s under 100 mW cm−1). In addition, the EHFs-based single-electrode triboelectric nanogenerators (TENG) give short-circuit transferred charge of 38.9 nC, open circuit voltage of 114.7 V, and short circuit current of 0.82 μA. More interestingly, the output voltage of TENG can be further increased via constructing the double triboelectrification layers. The comprehensive ability for harvesting various energies of the EHFs promises their potential to satisfy the corresponding requirements.

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A Stretchable, Self-Healable Triboelectric Nanogenerator as Electronic Skin for Energy Harvesting and Tactile Sensing

Materials ◽

10.3390/ma14071689 ◽

2021 ◽

Vol 14 (7) ◽

pp. 1689

Author(s):

Xi Han ◽

Dongjie Jiang ◽

Xuecheng Qu ◽

Yuan Bai ◽

Yu Cao ◽

...

Keyword(s):

Energy Harvesting ◽

Material Selection ◽

Short Circuit ◽

Red Light ◽

Short Circuit Current ◽

Open Circuit ◽

Triboelectric Nanogenerator ◽

Tactile Sensing ◽

Electronic Skin ◽

Self Powered

Electronic skin that is deformable, self-healable, and self-powered has high competitiveness for next-generation energy/sense/robotic applications. Herein, we fabricated a stretchable, self-healable triboelectric nanogenerator (SH-TENG) as electronic skin for energy harvesting and tactile sensing. The elongation of SH-TENG can achieve 800% (uniaxial strain) and the SH-TENG can self-heal within 2.5 min. The SH-TENG is based on the single-electrode mode, which is constructed from ion hydrogels with an area of 2 cm × 3 cm, the output of short-circuit transferred charge (Qsc), open-circuit voltage (Voc), and short-circuit current (Isc) reaches ~6 nC, ~22 V, and ~400 nA, and the corresponding output power density is ~2.9 μW × cm−2 when the matching resistance was ~140 MΩ. As a biomechanical energy harvesting device, the SH-TENG also can drive red light-emitting diodes (LEDs) bulbs. Meanwhile, SH-TENG has shown good sensitivity to low-frequency human touch and can be used as an artificial electronic skin for touch/pressure sensing. This work provides a suitable candidate for the material selection of the hydrogel-based self-powered electronic skin.

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Investigation of Position Sensing and Energy Harvesting of a Flexible Triboelectric Touch Pad

Nanomaterials ◽

10.3390/nano8080613 ◽

2018 ◽

Vol 8 (8) ◽

pp. 613 ◽

Cited By ~ 16

Author(s):

Tao Chen ◽

Qiongfeng Shi ◽

Kunpu Li ◽

Zhan Yang ◽

Huicong Liu ◽

...

Keyword(s):

Energy Harvesting ◽

Short Circuit ◽

Electronic Devices ◽

Maximum Output Power ◽

Short Circuit Current ◽

Open Circuit ◽

Triboelectric Nanogenerator ◽

Maximum Output ◽

Current Output ◽

Position Sensing

Triboelectric nanogenerator (TENG) is a promising technology because it can harvest energy from the environment to enable self-sustainable mobile and wearable electronic devices. In this work, we present a flexible touch pad capable of detecting the contact location of an object and generating substantial energy simultaneously based on the coupling of triboelectric effects and electrostatic induction. The touch pad consists of Polytetrafluoroethylene (PTFE) thin film, multiple Aluminum (Al) electrodes and Polyethylene terephthalate (PET) layers, which can be achieved through low cost, simplified and scalable fabrication process. Different from the conventional multi-pixel-based positioning sensor (i.e., large array of sensing elements and electrodes), the analogue method proposed here is used to implement the positioning function with only four electrodes. Position location can achieve a detecting resolution of as small as 1.3 mm (the size of locating layer is 7.5 cm × 7.5 cm). For the energy harvesting part, a multilayer structure is designed to provide higher current output. The open circuit voltage of the device is around 420 V and the short circuit current can reach up to 6.26 µA with current density of 0.25 µA/cm2. The maximum output power obtained is approximately 10 mW, which is 0.4 mW/cm2. The flexibility and significantly reduced number of electrodes enable the proposed touch pad to be readily integrated into portable electronic devices, such as intelligent robots, laptops, healthcare devices, and environmental surveys, etc.

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Development of the Triboelectric Nanogenerator Using a Metal-to-Metal Imprinting Process for Improved Electrical Output

Micromachines ◽

10.3390/mi9110551 ◽

2018 ◽

Vol 9 (11) ◽

pp. 551 ◽

Cited By ~ 14

Author(s):

Moonwoo La ◽

Jun Choi ◽

Jeong-Young Choi ◽

Taek Hwang ◽

Jeongjin Kang ◽

...

Keyword(s):

Short Circuit ◽

Short Circuit Current ◽

Contact Layer ◽

Open Circuit ◽

Triboelectric Nanogenerator ◽

Output Performance ◽

Triboelectric Nanogenerators ◽

Electrical Induction ◽

Advantageous Effect ◽

Electrical Output

Triboelectric nanogenerators (TENG), which utilize contact electrification of two different material surfaces accompanied by electrical induction has been proposed and is considered as a promising energy harvester. Researchers have attempted to form desired structures on TENG surfaces and successfully demonstrated the advantageous effect of surface topography on its electrical output performance. In this study, we first propose the structured Al (SA)-assisted TENG (SA-TENG), where one of the contact layers of the TENG is composed of a structured metal surface formed by a metal-to-metal (M2M) imprinting process. The fabricated SA-TENG generates more than 200 V of open-circuit voltage and 60 µA of short-circuit current through a simple finger tapping motion. Given that the utilization of the M2M imprinting process allows for the rapid, versatile and easily accessible structuring of various metal surfaces, which can be directly used as a contact layer of the TENG to substantially enhance its electrical output performance, the present study may considerably broaden the applicability of the TENG in terms of its fabrication standpoint.

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Fluttering Amplitude Amplification by Utilizing Flapping Moment in Flutter-Driven Triboelectric Nanogenerator

ASME 2021 15th International Conference on Energy Sustainability ◽

10.1115/es2021-62501 ◽

2021 ◽

Author(s):

Yi Zhang ◽

Ka Chung Chan ◽

Sau Chung Fu ◽

Christopher Yu Hang Chao

Keyword(s):

Flow Velocity ◽

High Speed ◽

Aerodynamic Force ◽

Short Circuit ◽

Short Circuit Current ◽

Open Circuit ◽

Energy Output ◽

Small Scale ◽

Triboelectric Nanogenerator ◽

Peak Value

Abstract Flutter-driven triboelectric nanogenerator (FTENG) is one of the most promising methods to harvest small-scale wind energy. Wind causes self-fluttering motion of a flag in the FTENG to generate electricity by contact electrification. A lot of studies have been conducted to enhance the energy output by increasing the surface charge density of the flag, but only a few researches tried to increase the converting efficiency by enlarging the flapping motion. In this study, we show that by simply replacing the rigid flagpole in the FTENG with a flexible flagpole, the energy conversion efficiency is augmented and the energy output is enhanced. It is found that when the flag flutters, the flagpole also undergoes aerodynamic force. The lift force generated from the fluttering flag applies a periodic rotational moment on the flagpole, and causes the flagpole to vibrate. The vibration of the flagpole, in turn amplifies the flutter of the flag. Both the fluttering dynamics of the flags with rigid and flexible flagpoles have been recorded by a high-speed camera. When the flag was held by a flexible flagpole, the fluttering amplitude and the contact area between the flag and electrode plates were increased. The energy enhancement increased as the flow velocity increased and the enhancement can be 113 times when the wind velocity is 10 m/s. The thickness of the flagpole was investigated. An optimal output of open-circuit voltage reaching 1128 V (peak-to-peak value) or 312.40 V (RMS value), and short-circuit current reaching 127.67 μA (peak-to-peak value) or 31.99 μA (RMS value) at 12.21 m/s flow velocity was achieved. This research presents a simple design to enhance the output performance of an FTENG by amplifying the fluttering amplitude. Based on the performance obtained in this study, the improved FTENG has the potential to apply in a smart city for driving electronic devices as a power source for IoT applications.

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Direct AFM-based nanoscale mapping and tomography of open-circuit voltages for photovoltaics

Beilstein Journal of Nanotechnology ◽

10.3762/bjnano.9.171 ◽

2018 ◽

Vol 9 ◽

pp. 1802-1808 ◽

Cited By ~ 6

Author(s):

Katherine Atamanuk ◽

Justin Luria ◽

Bryan D Huey

Keyword(s):

Solar Cells ◽

Open Circuit Voltage ◽

Short Circuit ◽

Photovoltaic Performance ◽

Three Dimensional ◽

Short Circuit Current ◽

Open Circuit ◽

Photovoltaic Properties ◽

Order Of Magnitude ◽

Individual Grains

The nanoscale optoelectronic properties of materials can be especially important for polycrystalline photovoltaics including many sensor and solar cell designs. For thin film solar cells such as CdTe, the open-circuit voltage and short-circuit current are especially critical performance indicators, often varying between and even within individual grains. A new method for directly mapping the open-circuit voltage leverages photo-conducting AFM, along with an additional proportional-integral-derivative feedback loop configured to maintain open-circuit conditions while scanning. Alternating with short-circuit current mapping efficiently provides complementary insight into the highly microstructurally sensitive local and ensemble photovoltaic performance. Furthermore, direct open-circuit voltage mapping is compatible with tomographic AFM, which additionally leverages gradual nanoscale milling by the AFM probe essentially for serial sectioning. The two-dimensional and three-dimensional results for CdTe solar cells during in situ illumination reveal local to mesoscale contributions to PV performance based on the order of magnitude variations in photovoltaic properties with distinct grains, at grain boundaries, and for sub-granular planar defects.

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Spiral Steel Wire Based Fiber-Shaped Stretchable and Tailorable Triboelectric Nanogenerator for Wearable Power Source and Active Gesture Sensor

Nano-Micro Letters ◽

10.1007/s40820-019-0271-3 ◽

2019 ◽

Vol 11 (1) ◽

Cited By ~ 37

Author(s):

Lingjie Xie ◽

Xiaoping Chen ◽

Zhen Wen ◽

Yanqin Yang ◽

Jihong Shi ◽

...

Keyword(s):

Electronic Device ◽

Short Circuit ◽

Steel Wire ◽

Average Power ◽

Short Circuit Current ◽

Human Motion ◽

Open Circuit ◽

Triboelectric Nanogenerator ◽

Single Finger ◽

Wearable Electronic Device

Abstract Continuous deforming always leads to the performance degradation of a flexible triboelectric nanogenerator due to the Young’s modulus mismatch of different functional layers. In this work, we fabricated a fiber-shaped stretchable and tailorable triboelectric nanogenerator (FST–TENG) based on the geometric construction of a steel wire as electrode and ingenious selection of silicone rubber as triboelectric layer. Owing to the great robustness and continuous conductivity, the FST–TENGs demonstrate high stability, stretchability, and even tailorability. For a single device with ~ 6 cm in length and ~ 3 mm in diameter, the open-circuit voltage of ~ 59.7 V, transferred charge of ~ 23.7 nC, short-circuit current of ~ 2.67 μA and average power of ~ 2.13 μW can be obtained at 2.5 Hz. By knitting several FST–TENGs to be a fabric or a bracelet, it enables to harvest human motion energy and then to drive a wearable electronic device. Finally, it can also be woven on dorsum of glove to monitor the movements of gesture, which can recognize every single finger, different bending angle, and numbers of bent finger by analyzing voltage signals.

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Hierarchical Honeycomb-Structured Electret/Triboelectric Nanogenerator for Biomechanical and Morphing Wing Energy Harvesting

Nano-Micro Letters ◽

10.1007/s40820-021-00644-0 ◽

2021 ◽

Vol 13 (1) ◽

Author(s):

Kai Tao ◽

Zhensheng Chen ◽

Haiping Yi ◽

Ruirong Zhang ◽

Qiang Shen ◽

...

Keyword(s):

Energy Harvesting ◽

Silver Nanowires ◽

Short Circuit ◽

Honeycomb Structure ◽

Open Circuit ◽

Wavy Surface ◽

Triboelectric Nanogenerator ◽

Morphing Wing ◽

Wafer Level ◽

Power Sources

AbstractFlexible, compact, lightweight and sustainable power sources are indispensable for modern wearable and personal electronics and small-unmanned aerial vehicles (UAVs). Hierarchical honeycomb has the unique merits of compact mesostructures, excellent energy absorption properties and considerable weight to strength ratios. Herein, a honeycomb-inspired triboelectric nanogenerator (h-TENG) is proposed for biomechanical and UAV morphing wing energy harvesting based on contact triboelectrification wavy surface of cellular honeycomb structure. The wavy surface comprises a multilayered thin film structure (combining polyethylene terephthalate, silver nanowires and fluorinated ethylene propylene) fabricated through high-temperature thermoplastic molding and wafer-level bonding process. With superior synchronization of large amounts of energy generation units with honeycomb cells, the manufactured h-TENG prototype produces the maximum instantaneous open-circuit voltage, short-circuit current and output power of 1207 V, 68.5 μA and 12.4 mW, respectively, corresponding to a remarkable peak power density of 0.275 mW cm−3 (or 2.48 mW g−1) under hand pressing excitations. Attributed to the excellent elastic property of self-rebounding honeycomb structure, the flexible and transparent h-TENG can be easily pressed, bent and integrated into shoes for real-time insole plantar pressure mapping. The lightweight and compact h-TENG is further installed into a morphing wing of small UAVs for efficiently converting the flapping energy of ailerons into electricity for the first time. This research demonstrates this new conceptualizing single h-TENG device's versatility and viability for broad-range real-world application scenarios.

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Self-Powered Acceleration Sensor Based on Multilayer Suspension Structure and TPU-RTV Film for Vibration Monitoring

Nanomaterials ◽

10.3390/nano11102763 ◽

2021 ◽

Vol 11 (10) ◽

pp. 2763

Author(s):

Xiaotao Han ◽

Qiyuan Zhang ◽

Junbin Yu ◽

Jinsha Song ◽

Zhengyang Li ◽

...

Keyword(s):

Short Circuit ◽

Mechanical Vibration ◽

Short Circuit Current ◽

Open Circuit ◽

Vibration Monitoring ◽

Triboelectric Nanogenerator ◽

Acceleration Sensor ◽

Vibration Acceleration ◽

Self Powered ◽

Suspension Structure

In this paper, we designed a triboelectric acceleration sensor with excellent multiple parameters. To more easily detect weak vibrations, the sensor was founded on a multilayer suspension structure. To effectively improve the electrical properties of the sensor, a surface roughening and internal doping friction film, which was refined with a room temperature vulcanized silicone rubber (RTV) and some thermoplastic polyurethanes (TPU) powder in a certain proportion, was integrated into the structure. It was found that the optimization of the RTV film increases the open circuit voltage and short circuit current of the triboelectric nanogenerator (TENG) by 223% and 227%, respectively. When the external vibration acceleration is less than 4 m/s2, the sensitivity and linearity are 1.996 V/(m/s2) and 0.999, respectively. Additionally, when it is in the range between 4 m/s2 and 15 m/s2, those are 23.082 V/(m/s2) and 0.975, respectively. Furthermore, the sensor was placed in a simulated truck vibration environment, and its self-powered monitoring ability validated by experiments in real time. The results show that the designed sensor has strong practical value in the field of monitoring mechanical vibration acceleration.

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