Irregular Wind Energy Harvesting by a Turbine Vent Triboelectric Nanogenerator and Its Application in a Self-Powered On-Site Industrial Monitoring System

Triboelectric Nanogenerator Drives Electrochemical Water Splitting for Hydrogen Production: Fundamentals, Progress, and Challenges

Currently, triboelectric nanogenerators (TENGs) are drawing significant attention owing to their potential in harvesting wave and wind energy from environment as well as their capability for driving electrochemical water splitting for hydrogen fuel production. This review aims to summarize the recent progress of ocean wave and wind energy harvesting TENGs and TENG-driven electrochemical water splitting processes for hydrogen evolution reaction. For better understanding, this review begins from the fundamentals of TENG and electrochemical water splitting. And then the working principle of TENGs and mechanism of electrochemical (EC) water splitting for hydrogen evolution reaction (HER) are introduced. Subsequently the progress of output performance enhancement in ocean wave and wind energy harvesting TENGs are systematically discussed including structure design, triboelectric material selection and power management all of which are important for output performance enhancement and the integration of TENGs with electrochemical water splitting cell. Although this review focus on the promotion strategies of TENG-driven electrochemical water splitting processes for HER, challenges for water splitting are also highlighted. While envision that this review provides a deep insight and direction to the design of TENG-driven electrochemical system for promoting the hydrogen fuel production in an active, economical manner.

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

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

A Blade-Type Triboelectric-Electromagnetic Hybrid Generator with Double Frequency Up-Conversion Mechanism for Harvesting Breeze Wind Energy

Triboelectric nanogenerators (TENGs) have garnered substantial attention in breeze wind energy harvesting. However, how to improve the output performance and reduce friction and wear remain challenging. To this end, a blade-type triboelectric-electromagnetic hybrid generator (BT-TEHG) with a double frequency up-conversion (DFUC) mechanism is proposed. The DFUC mechanism enables the TENG to output a high-frequency response that is 15.9 to 300 times higher than the excitation frequency of 10 to 200 rpm. Coupled with the collisions between tribomaterials, a higher surface charge density and better generating performance are achieved. The magnetization direction and dimensional parameters of the BT-TEHG were optimized, and its generating characteristics under varying rotational speeds and electrical boundary conditions were studied. At wind speeds of 2.2 and 10 m/s, the BT-TEHG can generate, respectively, power of 1.30 and 19.01 mW. Further experimentation demonstrates its capacity to charge capacitors, light up light emitting diodes (LEDs), and power wireless temperature and humidity sensors. The demonstrations show that the BT-TEHG has great potential applications in self-powered wireless sensor networks (WSNs) for environmental monitoring of intelligent agriculture.

Sustainable Sea of Internet of Things: Wind Energy Harvesting System for Unmanned Surface Vehicles

Harvesting wind energy from the environment and integrating it with the internet of things and artificial intelligence to enable intelligent ocean environment monitoring are effective approach. There are some challenges that limit the performance of wind energy harvesters, such as the larger start-up torque and the narrow operational wind speed range. To address these issues, this paper proposes a wind energy harvesting system with a self-regulation strategy based on piezoelectric and electromagnetic effects to achieve state monitoring for unmanned surface vehicles (USVs). The proposed energy harvesting system comprises eight rotation units with centrifugal adaptation and four piezoelectric units with a magnetic coupling mechanism, which can further reduce the start-up torque and expand the wind speed range. The dynamic model of the energy harvester with the centrifugal effect is explored, and the corresponding structural parameters are analyzed. The simulation and experimental results show that it can obtain a maximum average power of 23.25 mW at a wind speed of 8 m/s. Furthermore, three different magnet configurations are investigated, and the optimal configuration can effectively decrease the resistance torque by 91.25% compared with the traditional mode. A prototype is manufactured, and the test result shows that it can charge a 2200 μF supercapacitor to 6.2 V within 120 s, which indicates that it has a great potential to achieve the self-powered low-power sensors. Finally, a deep learning algorithm is applied to detect the stability of the operation, and the average accuracy reached 95.33%, which validates the feasibility of the state monitoring of USVs.

Triboelectric Nanogenerator-Enabled Digital Twins in Civil Engineering Infrastructure 4.0: A Comprehensive Review

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

Small wind turbines and their potential for internet of things applications

Wind energy is crucial for meeting climate and energy sustainability targets. Small wind turbines (SWTs) have gained significant attention due to their size and adaptability. These turbines have potential for Internet of Things (IoT) applications, particularly in powering large areas and low-power devices. This review examines SWTs for IoT applications, providing an extensive overview of their development, including wind energy rectifiers, power generation mechanisms, and IoT applications. The paper summarizes and compares different types of wind energy rectifiers, explores recent advancements and representative work, and discusses applicable generator systems such as electromagnetic, piezoelectric, and triboelectric nanogenerators. In addition, it thoroughly reviews the latest research on IoT application scenarios, including transportation, urban environments, intelligent agriculture, and self-powered wind sensing. Lastly, the paper identifies future research directions and emphasizes the potential of interdisciplinary technologies in driving SWT development.

Multidiscipline Applications of Triboelectric Nanogenerators for the Intelligent Era of Internet of Things

In the era of 5G and the Internet of things (IoTs), various human-computer interaction systems based on the integration of triboelectric nanogenerators (TENGs) and IoTs technologies demonstrate the feasibility of sustainable and self-powered functional systems. The rapid development of intelligent applications of IoTs based on TENGs mainly relies on supplying the harvested mechanical energy from surroundings and implementing active sensing, which have greatly changed the way of human production and daily life. This review mainly introduced the TENG applications in multidiscipline scenarios of IoTs, including smart agriculture, smart industry, smart city, emergency monitoring, and machine learning-assisted artificial intelligence applications. The challenges and future research directions of TENG toward IoTs have also been proposed. The extensive developments and applications of TENG will push forward the IoTs into an energy autonomy fashion.

Self-Powered High-Voltage Recharging System for Removing Noxious Tobacco Smoke by Biomimetic Hairy-Contact Triboelectric Nanogenerator

The most common size range of particulate matter (PM) in tobacco smoke is 1.0 to 5.0 microns; however, a high number of the most harmful PM is as small as 0.5 micron that is a serious threat to human health, and it is difficult to remove. There is an urgent need to develop a new purification technology for high-efficiency removing tobacco smoke with easily construction and low cost. Here, a method of self-powered high-voltage recharging system is demonstrated by designing biomimetic hairy-contact triboelectric nanogenerator (BHC-TENG) for long-lasting adsorption with a wide range from PM 0.5 to PM 10. The open-circuit voltage of BHC-TENGs reaches 8.42 KV, which can continuously charge injection to the melt-blown fabric, whose surface potential is able to maintain nearly 260 V level and create a uniform electrostatic adsorption field on the surface. This high-voltage recharging system reduces the concentration of PMs to World Health Organization (WHO) standards, maintaining the purification efficiency of PM 0.5- PM 10 persistently over 90%.

Novel 3D Printed Vortex-like Flexible Roller-Compacted Triboelectric Nanogenerator for Self-Powered Electrochemical Degradation of Organic Contaminants

It is an ideal way to use triboelectric nanogenerators (TENGs) to capture energy from the environment for the degradation of organic contaminants in water as a zero-carbon pathway. However, there is an urgent need to further develop TENGs with a simple structure and high output power. Herein, a novel TENG with a vortex-like flexible self-recovery blades of inner stator (denoted as VFR-TENG) is designed and manufactured with the assistance of a fused deposition modeling 3D printing technology. With the rotation of the outer rotor, a facile rotating contact-separation mode is achieved by the alternating arrangement of the flexible self-recovery blades. The contact tightness of the friction layer, a key factor for the transfer of charge density, can be easily adjusted by the thickness and arrangement style of the flexible self-recovery blades. The regulation of material elasticity and rotational frequency on the output characteristics is further investigated based on the special flexible structure. The VFR-TENG exhibits an instantaneous short-circuit current of 350 μA, an open-circuit voltage of 650 V, a transferred charge of 1.1 μC, and an optimum output power density of 4.4 W·m^-2. This high-performance VFR-TENG is used for electrochemical degradation systems, which achieves excellent degradation efficiencies of 88.9, 91.7, and 94.1% for methylene blue, methyl orange, and malachite green within 150 min, respectively. This work provides a new idea for the design of flexible self-recovery contact-separation TENGs, which is of great inspiration for the exploitation of TENGs with both the high peak current and high-frequency characteristics for efficient water treatment.

Flexible alternating current electroluminescent devices integrated with high voltage triboelectric nanogenerators

Flexible alternating current electroluminescent (ACEL) devices have attracted growing interest as promising wearable displays for their uniformity of light emission, low power consumption, and excellent reliability. However, the requirement of high-voltage power sources for driving ACEL devices greatly impedes their portability and commercialization. Here, we developed flexible ACEL devices integrated with high output-voltage triboelectric nanogenerators (TENG) using easy and low-cost crumpled Al electrodes. The output voltage and current could reach as high as 490 V and 71.74 μA, corresponding to the maximum instantaneous output power density of 1.503 mW cm^-2, which was demonstrated to power an integrated flexible ACEL patterned display. In addition, through signal acquisition and transmission, ACEL can display the compression frequency of TENG in real time. Such self-powered ACEL devices are very promising as flexible displays in wearable electronics.