Triboelectric Nanogenerators: Design, Fabrication, Energy Harvesting, and Portable-Wearable Applications

Scavenging energy from our day-to-day activity into useful electrical energy be the best solution to solve the energy crisis. This concept entirely reduces the usage of batteries, which have a complex issue in recycling and disposal. For electrical harvesting energy from vibration energy, there are few energy harvesters available, but the fabrication, implementation, and maintenances are quite complicated. Triboelectric nanogenerators (TENG) having the advantage of accessible design, less fabrication cost, and high energy efficiency can replace the battery in low-power electronic devices. TENGs can operate in various working modes such as contact-separation mode, sliding mode, single-electrode mode, and free-standing mode. The design of TENGs with the respective operating modes employed in generating electric power as well as can be utilized as a portable and wearable power source. The fabrication of triboelectric layers with micro-roughness could enhance the triboelectric charge generation. The objective of this chapter is to deal with the design of triboelectric layers, creating micro structured roughness using the soft-lithographic technique, fabrication of TENGs using different working modes, energy harvesting performance analysis, powering up commercial devices (LEDs, displays, and capacitors), and portable-wearable applications

Roadmap on energy harvesting materials

Ambient energy harvesting has great potential to contribute to sustainable development and address growing environmental challenges. Converting waste energy from energy-intensive processes and systems (e.g. combustion engines and furnaces) is crucial to reducing their environmental impact and achieving net-zero emissions. Compact energy harvesters will also be key to powering the exponentially growing smart devices ecosystem that is part of the Internet of Things, thus enabling futuristic applications that can improve our quality of life (e.g. smart homes, smart cities, smart manufacturing, and smart healthcare). To achieve these goals, innovative materials are needed to efficiently convert ambient energy into electricity through various physical mechanisms, such as the photovoltaic effect, thermoelectricity, piezoelectricity, triboelectricity, and radiofrequency wireless power transfer. By bringing together the perspectives of experts in various types of energy harvesting materials, this Roadmap provides extensive insights into recent advances and present challenges in the field. Additionally, the Roadmap analyses the key performance metrics of these technologies in relation to their ultimate energy conversion limits. Building on these insights, the Roadmap outlines promising directions for future research to fully harness the potential of energy harvesting materials for green energy anytime, anywhere

Contact-electrification enabled water-resistant triboelectric nanogenerators as demonstrator educational appliances

Triboelectric nanogenerators (TENG) work on the principle of tribo and contact electrification, which is a common phenomenon observed in daily life. TENGs are moving closer to commercialization, particularly for small scale energy harvesting and self-powered sensing. The toys and games industry has attracted a large audience recently with the introduction of digital toys. In this paper we embedded TENGs to power up a toy and operate during its specific application. We have modified two potential electronic demonstrator applications using TENG for lobster toy (LT-TENG) and stress ball (SB-TENG) device. The LT-TENG device generates a maximum electrical response of 60 V/2 µ A, with a power of 55 µ W and power density of 0.065 µ W m ^−2 at a load resistance value of 10 MΩ. Similarly, the SB-TENG device made of aluminum and PDMS as the triboelectric layers generates a maximum electrical output response of 800 V and 4 µ A peak to peak current with an instantaneous power of 6 mW and a power density of 3.5 mW m ^−2 respectively at a load resistance of 10 MΩ. In addition, the layers of the TENGs are packed with polyethylene to maintain the performance of the nanogenerator under harsh environmental conditions, especially with humid environments. The water resistance studies proved that the packed SB-TENG is impervious to water. The LT-TENG device is accompanied by four LEDs, and the device lights up upon actuating the handle. The SB is connected with the measuring instrument to record the quantity of force at which the SB is pressed. The adopted approach paves the way to convert these traditional toys into battery-free electronic designs and its commercialization

A review on the next generation of healing: Exploring the use of triboelectric nanogenerators in wound care

Despite advancements in wound healing treatments, high rates of elimination persist and emphasize the need for more effective solutions. One promising approach is using electrical stimulation (ES) therapy, which is underutilized in clinical practice. However, with the rise of wearable technology, ES therapy is gaining renewed attention. The triboelectric nanogenerator (TENG) converts mechanical energy into electricity following triboelectrification and electrostatic induction. With a variety of materials and device designs, TENG offers many benefits, including high output power. The small vibrations produced by the body and organs provide an excellent energy source for self-powered healthcare applications using TENG. This review highlights the progress made in TENG-based wound healing. We have summarized various research outcomes of TENG-based wound healing applications that have been published in recent years. However, challenges of TENG, such as downsizing, encapsulation, and stable performance, must be addressed before medical trials begin. In the coming years, addressing these challenges would pave the way for TENG to become an alternative power source for self-power wound healing applications. © 2023 Elsevier B.V.FALS

Battery-Free Electronic Smart Toys: A Step toward the Commercialization of Sustainable Triboelectric Nanogenerators

Next-generation toys are designed to entertain and interact with children. Such toys need a power source, generally a battery that must be replaced frequently, leading to increased maintenance costs. Recently, an innovative biomechanical energy harvester called a triboelectric nanogenerator (TENG) was introduced as an eco-friendly generator that scavenges waste energy. Here, in a step toward the commercialization of TENG devices, we present a novel approach that uses TENG technology to develop battery-free electronic smart toys. This robust, eco-friendly, and cost-effective approach for harnessing biomechanical energy can transform a traditional toy into a smart toy. With this innovative idea, we developed a smart clapping toy (SCT-TENG) and a smart duck toy (SDT-TENG) using biocompatible materials. We employed a simple inbuilt circuit with light-emitting diodes that are powered using biomechanical energy. The SCT-TENG and SDT-TENG exhibited output voltages of 65 V_p‑p and 260 V_p‑p, respectively. We believe that the use of TENG technology for battery-free electronic smart toys opens up new possibilities for the commercialization of TENGs and the field of battery-free smart toys

Battery-Free Electronic Smart Toys: A Step toward the Commercialization of Sustainable Triboelectric Nanogenerators

Next-generation toys are designed to entertain and interact with children. Such toys need a power source, generally a battery that must be replaced frequently, leading to increased maintenance costs. Recently, an innovative biomechanical energy harvester called a triboelectric nanogenerator (TENG) was introduced as an eco-friendly generator that scavenges waste energy. Here, in a step toward the commercialization of TENG devices, we present a novel approach that uses TENG technology to develop battery-free electronic smart toys. This robust, eco-friendly, and cost-effective approach for harnessing biomechanical energy can transform a traditional toy into a smart toy. With this innovative idea, we developed a smart clapping toy (SCT-TENG) and a smart duck toy (SDT-TENG) using biocompatible materials. We employed a simple inbuilt circuit with light-emitting diodes that are powered using biomechanical energy. The SCT-TENG and SDT-TENG exhibited output voltages of 65 V_p‑p and 260 V_p‑p, respectively. We believe that the use of TENG technology for battery-free electronic smart toys opens up new possibilities for the commercialization of TENGs and the field of battery-free smart toys

Sustainable Biomechanical Energy Scavenger toward Self-Reliant Kids’ Interactive Battery-Free Smart Puzzle

Biomechanical energy is a promising renewable energy source and, owing to the demand for portable and smart device power sources, has attracted the attention of researchers in a wide range of disciplines. We present a smart puzzle triboelectric nanogenerator (SP-TENG) based on the contact and separation mode between a surface-modified polydimethylsiloxane film and a paper contact material. The SP-TENG exhibits a simple structure (thin and lightweight), with an output voltage of 70 V and a current of 6.5 μA, which can drive a liquid crystal display at the press of a finger. A systematic investigation of the SP-TENG demonstrated it to be a practical energy harvester with the potential to charge a commercial capacitor and drive a liquid crystal display. The SP-TENG also acts as an instantaneous force sensor with detection sensitivity of 2.605 μA kPa^–1. We fabricated six SP-TENGs as puzzle pieces and formed a self-powered smart puzzle by connecting it to a simple logic circuit. This approach improved a simple traditional puzzle, transforming it into an interactive smart puzzle

Direct In Situ Hybridized Interfacial Quantification to Stimulate Highly Flexile Self-Powered Photodetector

In contrary to the existing externally powered photodetectors, a reliable approach for self-powered photodetection is designed for the first time through an internally integrated concept via coupling of piezotronic with photonic effects. A flexile self-powered photodetector (F-SPPD) developed by one-dimensionally grown floral-like F-ZnO nanorods on a poly­(vinylidene difluoride) substrate conjointly performs the tunability of optical properties through the exploitation of strain-induced piezoelectric potentials (σ⁺, σ^–) at the electrode interfaces. The experimental observation showed an ideal photodetector characteristics with a 1-fold increment in photoresponsivity (<i>R</i>_365nm ∼ 22.76 mA/W) by lowered Schottky barrier heights (Φ_SB1^T, Φ_SB2^T) through externally governed tensile strain (+ε). Further, the self-powered operation mode of F-SPPD exhibited higher spectral sensitivity (5.69 mA/(W cm^–2)) than that of the photodetector (3.47 mA/(W cm^–2)) operated under unstrained condition. This work effectively brings in the direct integration ideology of two different systems into a single module toward the downscaling of device size and weight

Smart maracas: an innovative triboelectric nanogenerator for earthquake detection and energy harvesting

In an era marked by a growing demand for sustainable energy solutions and resilient disaster management systems, the convergence of innovative technologies holds the promise of addressing multifaceted challenges. This manuscript explores the multifunctional capabilities of the "smart maracas", a novel triboelectric nanogenerator (TENG) designed to harvest mechanical energy and simultaneously serve as an earthquake sensor. The smart maracas is a striking example of the potential of TENGs to harness mechanical motion for practical applications. The device converts mechanical energy into electrical power through meticulous engineering, opening avenues for self-sustaining power sources in various domains. The manuscript outlines the device's structural design, working principle, and real-time applications, spanning bio-mechanical energy harvesting, vibrational energy scavenging, rotational energy harvesting, and a unique sensing application for door monitoring. A pivotal aspect of this research revolves around the smart maracas' role as an earthquake sensor. Rigorous experiments were conducted to assess the device's responsiveness to simulated seismic forces. Notably, a linear relationship with an R² value of 0.9989 was established between the voltage generated by the smart maracas and seismic acceleration. This remarkable correlation underscores the device's precision and reliability in detecting seismic events, opening doors for cost-effective earthquake monitoring solutions

Wearable Triboelectric Nanogenerator from Waste Materials for Autonomous Information Transmission via Morse Code

Electronic waste produced by plastic, toxic, and semiconducting components of existing electronic devices is dramatically increasing environmental pollution. To overcome these issues the use of eco-friendly materials for designing such devices are attaining great concern. This current work presents a recycled materials-based triboelectric nanogenerator (TENG) made of plastic waste and carbon-coated paper wipes (C@PWs), in which the PWs also collected from a waste bin. The resultant C@PWs-based TENG is then used for powering low-power electronic devices, and later, to generate a Morse code from a wearable for autonomous communication. Other end-users in a customized LabVIEW programme decode the Morse code signals and read the transmitted message. With further redesigning, a 9-segment keyboard is developed using nine-TENGs, connected to an Arduino controller to display the 9-segment actuation on a computer screen. Based on the above analysis, our C@PW-TENG device is expected to have an impact on future self-powered sensors and IoT systems