Self-powered Energy Harvesting Research Articles

Self-Powered Collaborative Energy Harvesting Interface Circuit for Stacked Multiple Piezoelectric Elements

Self-Powered Collaborative Energy Harvesting Interface Circuit for Stacked Multiple Piezoelectric Elements

A self-powered and self-sensing wave energy harvester based on a three-rotor motor of axle disk type for sustainable sea

The abundance of wave energy resources on ocean islands renders them an ideal natural platform for ocean monitoring. This is because the energy from the waves can be harnessed to power ocean monitoring sensors. This paper presents a self-powered and self-sensing three-stage rotor electromagnetic generator wave energy harvester (SS-WEH). The novel three-stage rotor generator configuration of the self-supply module demonstrates a superior power output compared to the single-rotor and inertial two-rotor structures used in previous studies. The maximum average power output achieved is 8.24 W within a frequency range of 1 Hz. PTO systems can achieve average power densities of up to 675 W/m³. Furthermore, the wave energy harvester functions as a self-sensing module, transmitting voltage signals to a computer terminal through a Wi-Fi module. This is achieved using a gated recirculation unit (GRU) deep learning model to monitor wave states and detect faults within the harvester system. The self-sensing module achieves an accuracy rate of 99.56 %. The wave energy harvester system proposed in this paper can simultaneously harvest wave energy, monitor ocean waves, and self-monitor system faults, which is crucial for advancing ocean resource development and monitoring.

A self-powered and self-sensing hybrid energy harvester for freight trains

Freight trains, being crucial for economic development, often face challenges due to the lack of electrical infrastructure. In this study, a self-powered and self-sensing hybrid energy harvester system (SS-HEH) is proposed, it consists of an electromagnetic generator (EMG), a piezoelectric energy harvester (PEH), and an energy input module. The proposed EMG utilizes a rolling magnet to intersect the square coil, thereby better adapting to the operational conditions of freight trains and producing higher electrical energy output. Additionally, the PEH converts bogie vibration signals into electrical signals to detect bogie operations. The EMG acts on the PEH, inducing bending and generating electrical signals. Conversely, the PEH acts on the EMG to maintain it horizontally, enhancing its ability to absorb the vibration energy of the bogie and forming a bistable system. Furthermore, at a speed of 40 km/h, the EMG voltage with PEH increased by 43.75 % compared to the scenario without PEH. The electrical performance of the SS-HEH was assessed through shake table experiments, yielding an RMS voltage of 11.5 V and output power of 74.1 mW. In addition, combined with deep learning, SS-HEH has an accuracy of 97.41 % in detecting the operating status of bogie.

Phytic acid-based super antifreeze multifunctional conductive hydrogel for human motion monitoring and energy harvesting devices

Conductive hydrogels have broad application prospects in the field of self-powered sensors and energy harvesting devices due to their good electrical conductivity and flexibility. However, at low temperatures, conductive hydrogels are usually frozen, resulting in problems such as poor electrical conductivity and flexibility, which seriously hinder the application of these fields. To address these challenges, phytic acid (PA) was employed as the crosslinker and antifreezing agent in this study. Polyvinyl alcohol (PVA), 2-acrylamido-2-methyl-1-propanesulfonic acid (AMPS), chitosan (CS), and PA were used as raw materials to successfully synthesize PVA/AMPS/CS/PA (PACP) multifunctional conductive hydrogels with outstanding antifreeze and water retention properties (freezing point below −80 °C, 30-day water loss rate of 3.5%). In addition, PACP hydrogels exhibit exceptional electrical conductivity of up to 9.4 S/m, along with antibacterial and biocompatible properties, enabling their utilization as wearable sensors on human skin tissue. Notably, the PACP hydrogel-based triboelectric nanogenerator (PACP-TENG) excels in accurately monitoring human motion and powering small electronic devices, facilitating remote control of small light switches. The resulting open circuit voltage is as high as 314 V at 25 °C and about 110 V at low temperature. Therefore, PACP hydrogels with excellent properties are expected to expand their applications in these fields.

A self-powered and self-monitoring ultra-low frequency wave energy harvester for smart ocean ranches

The ocean ranch environment contains ultra-low-frequency wave energy that can be utilized for powering low-power equipment. Therefore, this article proposes a smart ocean ranch self-powered and self-monitoring system (SOR-SSS) which consists of several key components: a mass pendulum ball (MPB), a commutation wheel system (CWS), an electromagnetic energy harvesting unit (EEHU), and four piezoelectric energy harvesting units (PEHU). Through six-degree-of-freedom vibration test bench experiments, the SOR-SSS achieved a maximum output power of 17.56 mW under a working condition of 0.4Hz, which was sufficient to power 152 LED lights. Additionally, by training the experimental base data using the LSTM algorithm, two different tasks were trained with a maximum accuracy of 99.72% and 99.80%, respectively. These results indicate that the SOR-SSS holds significant potential for collecting and predicting ultra-low-frequency blue energy. It can provide an effective energy supply and monitoring solution for smart ocean ranch.

Dissolvable photovoltaic cells on hydrogel

Solar energy is potentially the largest source of renewable energy for providing electrical power for human society. However, significant advances are required to make photovoltaic technologies have a low-carbon footprint in manufacture, be environmentally friendly at the end of their lives through recyclability, and be biodegradable. Here we report dissolvable organic photovoltaic devices based on poly(2-hydroxyethyl methacrylate), which show equal power conversion efficiency to their glass substrate-based counterparts. We use a novel method of including smectic liquid crystal (7-dioctyl[1]benzothieno[3,2- b][1]benzothiophene, C8-BTBT) as a crystal phase regulator in the heterojunction donor:acceptor polymer system to maintain the disposable organic solar cell efficiency without pre- or post-thermal annealing. The results show strong promise not only for more sustainable solar-cell fabrication but also as disposable and biocompatible solar cells for self-powered (energy harvesting) wearable and biomedical devices.

A compact self-powered inductor-less piezoelectric energy harvesting circuit using gyrator

In traditional low-frequency energy harvesting circuits, a large matched inductor with a large size is unavoidable. To reduce the size of the circuit, this paper proposes a compact self-powered inductor-less high-efficiency piezoelectric energy harvesting circuit using a low-power-consumption gyrator. A self-powered floating gyrator inductor is used in place of an inductor in the proposed circuit, and the required phasor response is acquired by using its voltage–current (V–I) relationship. The proposed circuit offers easy adjustability and performance benefits in small integrated circuits packages. The proposed circuit can be cost-effective and provide reduced area advantages in autonomous self-powered Internet-of-Things and wireless sensor nodes applications. Regarding harvested energy, the proposed circuit with a storage capacitor of 0.24 F can obtain 320% improved performance than standard energy harvesting along with the lowest power consumption of 0.25 µW in self-powered operation. The proposed technique can also be applied to similar piezoelectric energy harvesting strategies with large inductors.

Self-powered multi-PZTs energy harvesting interface based on extensible PSSHI rectification with power region optimization technique

Self-powered multi-PZTs energy harvesting interface based on extensible PSSHI rectification with power region optimization technique

Self-powered piezoelectric energy harvesting with ultra-low power consumption for low-amplitude ambient vibrations

Self-powered piezoelectric energy harvesting with ultra-low power consumption for low-amplitude ambient vibrations

The nexus of sustainable fisheries: A hybrid self-powered and self-sensing wave energy harvester

Wave energy harvesters (WEHs) are an effective solution to the problem of powering sensors in marine fisheries. A future direction for WEHs is to achieve wave monitoring while meeting the power requirements of the sensors. This paper presents a hybrid self-powered and self-sensing wave energy harvester (HSS-WEH), which consists of three modules: an energy input module, a self-powered module, and a self-sensing module. In this study, an eccentric pendulum is used to capture low-frequency irregular wave energy. The proposed rectification enhancement mechanism (REM) converts the bidirectional rotation of the spindle into the unidirectional rotation of the magnet flywheel. In addition, a triboelectric nanogenerator based on rolling PTFE balls is used to convert wave information into electrical signals for wave monitoring. The optimization of the mass of the eccentric pendulum was achieved through a six-degree-of-freedom platform experiment. At 0.3 Hz, the electromagnetic generator power with REM is enhanced by 36.11 % to 7.84 mW than without REM. Furthermore, the self-sensing module achieves a high level of accuracy, reaching 98.62 % in identifying the risk level of the waves. Water tank experiments and energy consumption analysis of sensors confirm the practical applicability of HSS-WEH in sustainable fisheries.

A self-powered and self-sensing knee negative energy harvester

Wearable devices realize health monitoring, information transmission, etc. In this study, the human-friendliness, adaptability, reliability, and economy (HARE) principle for designing human energy harvesters is first proposed and then a biomechanical energy harvester (BMEH) is proposed to recover the knee negative energy to generate electricity. The proposed BMEH is mounted on the waist of the human body and connected to the ankles by ropes for driving. Double-rotor mechanism and half-wave rectification mechanism design effectively improves energy conversion efficiency with higher power output density for more stable power output. The experimental results demonstrate that the double-rotor mechanism increases the output power of the BMEH by 70% compared to the single magnet-rotor mechanism. And the output power density of BMEH reaches 0.07 W/kg at a speed of 7km/h. Furthermore, the BMEH demonstrates the excitation mode detection accuracy of 99.8% based on the Gate Recurrent Unit deep learning model with optimal parameters.

Janus CoMOF-SEBS Membrane for Bifunctional Dielectric Layer in Triboelectric Nanogenerators.

Considerable research has been conducted on the application of functional nano-fillers to enhance the power generation capabilities of triboelectric nanogenerators (TENGs). However, these additives often exhibit a decrease in output power at higher concentration. Here, a Janus cobalt metal-organic framework-SEBS (JCMS) membrane is reported as a dual-purpose dielectric layer capable of efficiently capturing and blocking charges for high-performance TENGs. The JCMS is produced asymmetrically through gravitational sedimentation, employing spherical CoMOFs within a diluted SEBS solution. Beyond its dual dielectric characteristics, the JCMS showcases exceptional mechanical durability, displaying notable stretchability of up to 475% and remarkable resilience when subjected to diverse mechanical pressures. Consequently, the JCMS-TENG produces a maximum peak-to-peak voltage of 936V, a current of 42.8µA, and a power density of 10.89Wm- 2 when exposed to an external force of 10N at a 5Hz frequency. This investigation highlights the potential of JCMS-TENGs with unique structures, known for their exceptional energy harvesting capabilities, mechanical strength, and flexibility. Additionally, the promising prospects of easily produced asymmetric structures is emphasized with bifunctionalities for developing efficient and flexible MOFs-based TENGs. These advancements are well-suited for self-powered wearables, rehabilitation devices, and energy harvesters.

Textured nanofibers inspired by nature for harvesting biomechanical energy and sensing biophysiological signals

Flexible electronics are emerging as a promising new platform for wearables; however, their practical utility is hindered by the limited battery life of electronic devices and the need for frequent battery replacements. Here, we report self-powered, flexible, permeable, tough, and lightweight biomechanical energy harvesting and biophysiological sensing devices using textured nanofibers for wearable electronics applications. The textured structure draws inspiration from two major sources of nature: the interior porous structure of jute fibers and the rough bark texture of trees. Interior pores are introduced to the nanofibers to increase compressibility and breathability like jute fibers. The inspiration from the rough bark texture also leads to a wrinkled surface morphology of the nanofibers to expand the surface area and consequently enhance toughness. To design and fabricate such a textured structure, the vapor-induced phase separation mechanism and electrospinning technique are employed within a controllable high humidity environment. Consequently, the textured nanofiber-based devices exhibit a well-rounded performance in electrical, mechanical, and physical properties, specifically demonstrating a significantly enhanced piezoelectric performance with more than two-fold electrical generation. These textured devices not only effectively harvest biomechanical energy from human movement but also demonstrate sensing capability for self-powered multifunctional biophysiological monitoring applications by leveraging the same piezoelectric mechanism. The novel design strategy for the textured nanofibers and their resultant balanced performance promotes the versatility and practical applicability of piezoelectric fibrous energy harvesting and sensing devices, contributing to the development of next-generation flexible and wearable electronics.

A State-of-the-Art Review of Hydronic Asphalt Solar Collector Technology for Solar Energy Harvesting on Road Pavement

Nature inspires innovative renewable energy solutions by advancing our road pavements, as the sun is the only infinite and accessible source of clean and green energy on our planet. In addition to the various solar energy production methods, a new paradigm for utilizing asphalt pavement as a solar collector is being developed for self-powered energy harvesting. Due to direct solar radiation, flexible paved surfaces exposed to direct sunlight can heat up to 70°C in the summer. The heat is then dissipated into the environment, causing the urban heat island effect, and accelerating thermal oxidation of asphalt pavement. This can lead to structural failure and reduced pavement performance. This study aims to present a state-of-the-art review of hydronic asphalt solar collectors (HASCs) and propose the best model to enhance the performance of asphalt solar collectors. The findings of the study concluded that asphalt has the potential to absorb solar energy and store heat energy. This can be achieved by assembling and modifying conventional asphalt structures into modern asphalt solar collector designs that consist of pipe arrangements below the paved surface filled with liquid flowing through the pavement surface. The study found that a significant limitation of previous research was that it focused on optimizing the temperature profile at various depths but did not focus on structural improvements to reduce failure and increase the performance of asphalt solar collectors. Therefore, this review study proposed a new technique of using conductive and waste materials to enhance the performance of asphalt solar collectors.

Highly positive fluorophlogopite for enhanced power generation in triboelectric nanogenerators prepared on a flexible Ni–Cu fabric

Recent developments in triboelectric nanogenerators (TENGs) facilitate creation of sustainable, self-powered energy harvesting systems. In our study, we introduce fluorophlogopite as a positive triboelectric material with excellent electron transfer capabilities. We investigate the efficacy of a fluorophlogopite-based TENG, MgF-mica-TENG. We use a simple spray method on flexible Ni–Cu conductive fabric platforms to perform electrical analyses including open-circuit voltage (Voc), short circuit current (Isc), and peak power density using a home-made, 3D-printed, M-shaped spring setup. MgF-mica-TENG exhibited enhanced performance compared to the conventional muscovite-based TENG (Al-mica-TENG). This enhanced performance is primarily attributed to the increased surface potential of fluorophlogopite, which facilitate efficient charge transfer upon the contact of two electrodes, combined with optimized 11fabrication parameters. Based on our findings, we anticipate that MgF-mica materials can pave the way to the development of a comprehensive strategy to powering smart electronics, harnessing the abundant mechanical energy sources found in our daily surroundings.

Enhancing Triboelectric Nanogenerator Performance with Metal–Organic-Framework-Modified ZnO Nanosheets for Self-Powered Electronic Devices and Energy Harvesting

Enhancing Triboelectric Nanogenerator Performance with Metal–Organic-Framework-Modified ZnO Nanosheets for Self-Powered Electronic Devices and Energy Harvesting

Polyvinyl alcohol-based economical triboelectric nanogenerator for self-powered energy harvesting applications

Triboelectric nanogenerators (TENGs) have emerged as a promising alternative for powering small-scale electronics without relying on traditional power sources, and play an important role in the development of the internet of things (IoTs). Herein, a low-cost, flexible polyvinyl alcohol (PVA)-based TENG (PVA-TENG) is reported to harvest low-frequency mechanical vibrations and convert them into electricity. PVA thin film is prepared by a simple solution casting technique and utilized to serve as the tribopositive material, polypropylene film as tribonegative, and aluminum foil as electrodes of the device. The dielectric-dielectric model is implemented with an arch structure for the effective working of the PVA-TENG. The device showed promising electrical output by generating significant open-circuit voltage, short-circuit current, and power . Also, PVA-TENG is subjected to a stability test by operating the device continuously for 5000 cycles. The result shows that, the device is mechanically durable and electrically stable. Further, the as-fabricated PVA-TENG is demonstrated to show feasible applications, such as charging two commercial capacitors with capacitances 1.1 and 4.7 μF and powering green light-emitting diodes. The stored energy in the 4.7 μF capacitor is utilized to power a digital watch and humidity and temperature sensor without the aid of an external battery. Thus, the PVA-TENG facilitates ease of fabrication, robustness, and cost-effective strategy in the field of energy harvesting for powering lower-grid electronics by demonstrating their potential as a sustainable energy source.

Dysprosium tungstate incorporated on exfoliated layered molybdenum disulfide-based a flexible and wearable piezoelectric nanogenerator for the dual purpose of self-powered energy harvesting and a smart mask for human breath monitoring

The rapid spread of the novel coronavirus (COVID-19), including the Omicron, and Delta variants, has resulted in severe economic losses and health issues worldwide. This crisis has particularly impacted the human respiratory system, demanding urgent solutions. With this goal in mind, we have developed a novel DyW@MoS2-based FPENG for self-powered energy harvesting and a smart mask for monitoring human breath. The highest piezoelectric response was observed at 30 wt% of FPENG (∼1.30 V), which is ∼1.9 times better than MoS2–PDMS FPENG. The generated voltages from the FPENG are used to charge capacitors, power the LEDs, and run a wristwatch. Additionally, the RS-FPENG is employed in real-time demonstrations as a self-powered smart mask for monitoring human breath. RS-FPENG showed ∼141 mV even ∼90% humidity, confirming that the water vapor generated doesn’t affect human breath monitoring. FFT results revealed that the RS-FPENG can distinguish between normal and fast breathing. By connecting the RS-FPENG to an LED circuit system, the glowing LED can be turned off when a person stops breathing. The fabricated smart mask exhibits excellent unique capabilities, including small size, simple fabrication, easy installation, and cost-effectiveness, making it suitable for respiratory system monitoring during the COVID-19 pandemic.

Superior piezoelectric performance of chemically synthesized transition metal dichalcogenide heterostructures for self-powered flexible piezoelectric nanogenerator

In addition to the superior electrical and optoelectronic attributes, ultrathin two-dimensional transition metal dichalcogenides (TMDCs) have evoked appreciable attention for their piezoelectric properties. In this study, we report, the piezoelectric characteristics of large area, chemically exfoliated TMDCs and their heterostructures for the first time, as verified by piezoelectric force microscopy measurements. Piezoelectric output voltage response of the MoS2-WSe2 heterostructure piezoelectric nanogenerator (PENG) is enhanced by ∼47.5% if compared with WSe2 and ∼29% if compared to MoS2 PENG, attributed to large band offset induced by heterojunction formation. This allows the scalable fabrication of self-powered energy harvesting PENGs, which can overcome the various shortcomings of complicated synthesis processes, complex fabrication steps, low yield, and poor stability. The fabricated flexible, self-powered MoS2-WSe2 heterostructure nanogenerator exhibits piezoelectric output ∼46 mV under a strain of ∼0.66% yielding a power output ∼12.3 nW, which offers better performance than other two-dimensional material based piezoelectric devices and also reveals the ability of bio-mechanical energy harvesting. This cost effective approach to fabricate eco-friendly MoS 2 -WSe 2 based fatigue free, superior performance piezoelectric-nanogenerators can be utilized to evolve flexible energy harvesting devices and may also be attractive as a self-powered, smart wearable sensor devices.

Flexible magnetoelectric PVDF–CoFe2O4 fiber films for self-powered energy harvesters

Integrating the concept of magnetoelectric in the mechanical energy harvesters through the magneto-mechano-electrical (MME) nanogenerators has been explored to realize the self-powered devices. The magnetoelectric interaction enabled the output performance of the MME nanogenerator under magnetic stimulus of the active components of the energy harvesters. In this perspective, we fabricated a flexible biomechanical and MME nanogenerator using PVDF/CoFe2O4 fibers composite films. CoFe2O4 fibers were synthesized by the electrospinning technique and the process parameters were optimized to achieve uniform and bead-free fibers. The structural and morphological properties were investigated through scanning electron microscopy (SEM), transmission electron microscopy (TEM), and atomic force microscopy (AFM). The structural and morphology revealed the fibers calcined at 800 °C with a heating rate of 2 °C/min produced bead-free continuous fibers with a fiber diameter of 210 nm with cubic spinel crystalline structure with a crystallite size of 34 nm. These highly crystalline fibers were used to fabricate PVDF/CoFe2O4 fibers composite films. The magnetoelectric behaviour of the films verified through polarization vs. electric field (P-E) loops under magnetic field. The leakage current density and mechanism of the composite films were investigated, and it was discovered that the mechanism was due to Schottky emission. Further the energy harvesting performance of the composite films were estimated where the nanogenerator achieved an output voltage of 13 V under biomechanical tapping force while the MME nanogenerator produced 3.5 V under a low frequency stray magnetic field of 6 Oe with a power density of 28 μW/m2.