The review, led by Premkumar Sharad Bhosale of the Daegu Gyeongbuk Institute of Science and Technology together with colleagues including Swati Panda, Dandugudumula Ramu, Sugato Hajra, Eunjoo Kim, and Hoe Joon Kim, surveys recent progress in TENG-based systems across machine fault detection, vibration monitoring, fluid flow control, air filtration, environmental monitoring, and mining safety. The authors emphasize that TENG devices are attractive for industrial deployment because they are self-powered, sustainable, inexpensive to fabricate, and compatible with flexible and even biodegradable materials. Their architecture can be tuned to many device layouts, and their electrical outputs integrate naturally with artificial intelligence and Internet of Things platforms, opening a path toward next-generation smart factories where sensors generate their own power and communicate autonomously.

At the heart of the technology is a simple physical mechanism. A typical TENG contains two dielectric layers with opposite triboelectric properties and two electrodes. When the layers come into contact, equal and opposite charges build at the surfaces. As the layers separate, electrons flow between the electrodes to balance the potential difference, producing a current. When the layers touch again, electrons flow in the reverse direction. This periodic motion generates an alternating electrical output that can be harvested, stored, and used to power small electronics. Researchers operate TENGs in four principal modes: contact-separation, single-electrode, lateral sliding, and freestanding. The freestanding mode is especially valuable for industrial use because the moving triboelectric layer never makes hard contact with the electrodes, minimizing surface wear and significantly extending device lifetime.

Among the most striking demonstrations is a vibrational TENG network developed by Li and colleagues for machine fault detection. The device stacked four contact-separation units with copper electrodes and polyethylene terephthalate triboelectric layers, producing an open-circuit voltage of 600 volts, a transferred charge of 0.85 microcoulombs, and a power density of 3.33 milliwatts per cubic meter. Connected through a power management module, microcontroller, and wireless transmitter, three self-powered vibration sensor nodes fed temperature and acceleration data into a support vector machine classifier, achieving 83.6 percent accuracy in detecting machine failures. The researchers point to smart factories, intelligent manufacturing, and continuous production monitoring as the most immediate applications for such networks.

Wind energy, often irregular and unpredictable inside industrial facilities, has also been harnessed. Zhang and co-workers built a turbine vent TENG integrating two freestanding-mode units and two contact-sliding-separation units on a conventional turbine vent. At a wind speed of seven meters per second, the device delivered 178.2 volts, a current of 38.2 microamperes, and 2.71 milliwatts of power, enough to light 120 green LEDs, charge a capacitor to drive a thermometer, and power a wireless alarm transmitter for early temperature warnings. In a complementary effort, Li and colleagues created a rotary wind-driven TENG that exploits the thermal response of nickel-titanium shape memory alloy to tune its contact area. At temperatures above 40 degrees Celsius, the alloy flattens and changes the electrical contact configuration, allowing the device to serve as a self-powered airflow temperature alarm for wind-cooled transformers, delivering an average power density of 140 milliwatts per square meter at twelve meters per second and a wind speed sensitivity of 0.526 microamps per meter per second.

Fluid control represents another frontier. Wang and colleagues developed a flapping-film TENG in which a soft fluorinated ethylene propylene film flutters between copper electrodes as air passes through a nozzle chamber, generating up to 32 volts and 2 microamps. Paired with an Arduino microcomputer, stepper motor, and blower, the system sensed and actively regulated airflow, with smoke visualization experiments at a Reynolds number of 8000 confirming precise control over flow fields. The researchers see direct applications in air conditioning, refrigeration, and production processes where real-time flow management matters. Meanwhile, Kisomi and colleagues applied contact-separation TENGs to air filtration, building industrial filters and face masks from polypropylene-polyurethane pairs that generated 10 to 20 kilovolts under airflow velocities between 1 and 5 centimeters per second. The electrostatic charging captured particles as small as PM0.1 with removal efficiencies reaching 99 percent at low airflow velocities, offering self-powered protection against industrial particulate pollution.

Vibration monitoring, a cornerstone of predictive maintenance, has been advanced by Jaurker and colleagues, who used laser micro-texturing on fluorinated ethylene propylene and aluminum layers to build a TENG producing 794 volts, 44 microamps, and a power density of 2371.6 microwatts per square centimeter. Mounted with an energy harvesting module charging a small battery, the device powered a Wi-Fi microcontroller that wirelessly transmitted vibration signatures to smart devices, instantly registering when a shaker turned on and off. For broader environmental surveillance, Zhang and co-workers introduced a pulsed TENG architecture that increases internal capacitance through an external capacitor, enhancing charge density while limiting open-circuit voltage. Coupled with a power management circuit and an LTC3588 converter, the platform periodically measured light intensity, temperature, humidity, and atmospheric pressure, transmitting data at intervals of seven minutes and thirty-five seconds. In mining, Liu and colleagues reported a triboelectric self-powered sensing platform in Nature Communications that detected wind speeds as low as 0.32 meters per second using a 3D-printed turbine with PTFE electret and conformal spiral electrodes, outperforming a commercial hot-wire anemometer in signal consistency over three months of field deployment, though cycle times lengthened from 64.9 to 196 seconds as the FEP and copper components degraded.

Despite these successes, the review is candid about the obstacles standing between laboratory prototypes and industrial reality. TENGs still suffer from relatively low power density, and their pulsed alternating output demands sophisticated rectification, storage, and regulation circuits to deliver stable direct-current power. Conventional polymers such as PTFE, PDMS, and Kapton generate strong triboelectric signals but wear down, degrade chemically, and lose charge under high pressure, temperature swings, oil contamination, and corrosive conditions. Humidity and thermal activity promote charge trapping and dissipation, and most durability studies have been confined to controlled laboratory settings rather than the harsh environments where these devices must ultimately survive. The authors call for scalable, low-cost fabrication routes such as soft lithography, laser ablation, roll-to-roll printing, and spray coating to produce industrial-grade devices that combine high output with mechanical robustness, alongside standardized evaluation benchmarks for performance, durability, and environmental resistance.

The path forward, the researchers argue, lies in hybridization and smarter materials. Combining TENGs with piezoelectric, electromagnetic, or photovoltaic harvesters could stabilize energy supply across dynamic industrial conditions, while biodegradable polymers such as silk fibroin, chitosan, polylactic acid, and polycaprolactone, reinforced with carbon nanomaterials, MXenes, or liquid-metal droplets, could raise charge density without sacrificing sustainability. Self-healing elastomers with dynamic covalent or supramolecular bonds promise autonomous recovery from mechanical damage, extending device lifetimes. Machine learning and artificial intelligence are expected to handle adaptive signal processing, predictive energy optimization, and autonomous fault diagnosis, while additive manufacturing and 3D and 4D printing could embed TENGs directly into robotic joints, machinery surfaces, and structural components. If these interdisciplinary threads converge, the authors conclude, triboelectric nanogenerators could become the self-sustaining nervous system of Industry 4.0, sensing, powering, and protecting the factories of the future without drawing a single external watt.

Subject of Research: Triboelectric nanogenerators for self-powered smart industrial sensing applications

Article Title: Triboelectric nanogenerators for smart industrial sensing applications

Article References: Bhosale, P. S., Panda, S., Ramu, D., Hajra, S., Kaja, K. R., Belal, M., Kim, E., & Kim, H. J. (2025). Triboelectric nanogenerators for smart industrial sensing applications. Advances in Industrial and Engineering Chemistry, 1(1), Article 40. https://doi.org/10.1007/s44405-025-00040-x

Image Credits: AI Generated

DOI: 10.1007/s44405-025-00040-x

Keywords: triboelectric nanogenerator, self-powered sensors, smart factory, energy harvesting, industrial IoT, vibration monitoring, machine fault detection, air filtration, power management, mining safety, Industry 4.0, nanogenerators

The clinical motivation is stark. Myopia has become one of the fastest-growing public health problems in the world, particularly among children and adolescents, and it is far more than a simple refractive error that glasses can fix. Progressive myopia involves excessive elongation of the eyeball, driven by a cascade that begins in the retina and ends in structural weakening of the sclera, the tough outer coat of the eye. Genetic susceptibility combines with environmental pressures such as prolonged near work, insufficient outdoor light exposure and abnormal retinal defocus to alter retinal neurotransmission, including dopamine signalling. These changes disturb the release of growth modulators such as retinoic acid, TGF-β and insulin-like growth factor, which in turn destabilize the balance of collagen synthesis and degradation in the sclera, mediated by matrix metalloproteinases and activated fibroblasts. The result is a thinner, softer sclera that deforms under normal intraocular pressure, stretching the eye axially and predisposing patients to retinal detachment, myopic macular degeneration and optic neuropathy.

SENGs attack this problem from a fundamentally different angle than conventional optical correction. The review divides the technology into two complementary classes. Piezoelectric nanogenerators, or PENGs, exploit materials such as zinc oxide nanowires, barium titanate nanoparticles and piezoelectric polymers like PVDF and its copolymer P(VDF-TrFE), in which mechanical deformation shifts internal charge distributions and creates a piezoelectric potential that drives current through an external circuit. Triboelectric nanogenerators, or TENGs, instead harvest charge generated when two materials with different electron affinities make contact and separate, an effect amplified by electrostatic induction. PENGs deliver moderate voltages with relatively higher current and suit implantable stimulation scenarios, while TENGs produce high open-circuit voltages at very low currents and excel in flexible wearable formats such as contact lenses and eyeglass-mounted sensors. Both operate comfortably within the mechanical regime of the eye, where a normal blink imposes roughly 2 to 5 kilopascals of pressure and forceful blinking can exceed 10 kilopascals.

The most striking preclinical demonstrations come from device prototypes that translate these physics into therapy. One electro-driven drug delivery system integrates barium titanate nanoparticles coated with atropine into an orthokeratology lens. When the wearer closes their eyes, eyelid pressure triggers the piezoelectric effect, generating transient microvoltages that are proposed to perturb the interfacial electrostatic equilibrium of the nanoparticles and promote atropine desorption. Release rates reach approximately 80 percent within 12 hours, with more release accumulating the longer the eyes remain closed, effectively synchronizing drug delivery with natural physiology. In guinea pig myopia models, this system achieved superior reversal of refractive error compared with atropine eye drops alone or combined lens-plus-drop regimens, increased choroidal blood flow velocity, and raised ocular tissue drug concentrations more than twenty-fold above blood levels without detectable systemic toxicity or ocular surface irritation.

Electrical stimulation itself may also remodel the diseased sclera. Inspired by the electrocyte discharge of electric eels, researchers developed a biomimetic piezoelectric patch called BPP@PVDF, made by spin-coating a piezoelectric PVDF membrane onto a bovine pericardium scaffold. Under physiological ocular deformation, the patch generates self-powered microcurrents that were associated with increased scleral fibroblast proliferation and type I collagen synthesis. In rabbit models of lens-induced myopia, eyes receiving the patch showed over 40 percent less axial elongation than sham-operated controls, along with denser and more regularly organized collagen fibers, 20 to 30 percent greater scleral tensile strength and no abnormalities in intraocular pressure, retina or cornea. The authors are careful to stress, however, that the intracellular signaling pathways connecting generated electricity to fibroblast activation remain incompletely defined, and long-term risks such as pathological fibrosis have not been systematically excluded.

Drug delivery to the back of the eye is a second major frontier. Intravitreal injections carry infection and retinal detachment risks, while non-invasive routes typically achieve delivery efficiencies below 5 percent. A wearable electric switch system comprising an electrically driven drug delivery lens and a flexible square-wave generator addresses this bottleneck by using electrical stimulation to transiently open junctions between retinal pigment epithelial cells, reducing resistance along the sclerochoroidal-retinal pathway. The system delivered immunoglobulin G with 14 percent efficiency, approaching the 16 percent achieved by intravitreal injection, enhanced macromolecular penetration three- to five-fold in rabbit eyes and worked across monoclonal antibodies, DNA origami and extracellular vesicles, with adjustable waveform parameters providing a controllable safety window.

The same physics also supports closed-loop sensing. Triboelectric sensors mounted on skin or eyeglasses can distinguish voluntary from involuntary blinks, decode eye movements in eight directions with micrometer spatial resolution, and monitor intraocular pressure with sensitivities of about 1.28 megahertz per millimeter of mercury. A wireless therapeutic contact lens platform integrating sensing, wireless communication and iontophoretic drug delivery has maintained stable intraocular pressure readings for up to two months in rabbits while delivering anti-glaucoma medication on demand. Combined with machine learning, such self-powered sensors could feed adaptive algorithms that adjust stimulation and drug-release parameters in real time, forming the basis of an intelligent feedback loop between the eye, external computation and therapy. The review notes that tellurium nanowire retinal nanoprostheses and the clinically validated PRIMA photovoltaic implant, while not energy harvesters themselves, provide powerful engineering templates for wireless neural interfacing and long-term biointegration that future SENG platforms can borrow.

Formidable challenges separate the laboratory from the clinic. The eye is a hostile environment for electronics: tear fluid shields surface charges, millions of blinks per year accelerate mechanical fatigue and delamination, and materials such as zinc oxide can dissolve and release cytotoxic ions, while lead-based piezoceramics pose obvious toxicity concerns that push designers toward lead-free alternatives like barium titanate and biodegradable polymers such as PLGA. A fundamental ‘power gap’ also persists, since blink-driven generators produce transient bursts rather than the continuous, tightly regulated currents needed for reliable neuromodulation, and patients with dry eye or impaired ocular motility generate too little biomechanical energy for dependable therapy. Hybrid devices that pair nanogenerators with miniature supercapacitors or thin-film batteries could buffer this variability. Regulatory pathways add another layer of complexity, because multifunctional platforms combining stimulation, drug delivery, biosensing and artificial intelligence will likely be classified as combination products requiring coordinated review of electrical safety, pharmacology, software reliability and cybersecurity. Pediatric use, the population that most needs myopia control, raises additional ethical and developmental concerns that will demand adult safety data first.

Even so, the trajectory is clear. Ophthalmic biomaterials are evolving from passive structural supports into dynamic, intelligent systems that sense, respond and adapt. By harvesting the eye’s own motion to power stimulation, drug release and continuous monitoring, self-generated electricity nanogenerators sketch a future in which myopia is actively managed as the progressive neurovascular disease it truly is, rather than passively corrected with lenses. If materials scientists, neuroscientists and clinicians can close the remaining gaps in energy stability, chronic biocompatibility and validated dosing, the review concludes, blinking may one day do far more than keep the eye wet. It could power the therapy that saves a child’s sight.

Subject of Research: Self-powered bioelectronic nanogenerators for myopia treatment and vision restoration

Article Title: Bioelectronic interfaces for restoring vision pathways

Article References: Wang, T., Zhao, B., Du, Y., Wu, S., Jiang, Y., Li, J., Miao, Y.-B., & Shi, Y. (2026). Bioelectronic interfaces for restoring vision pathways. Materials Today Bio, 40, Article 103652. https://doi.org/10.1016/j.mtbio.2026.103652

Image Credits: AI Generated

DOI: 10.1016/j.mtbio.2026.103652

Keywords: myopia, nanogenerators, triboelectric, piezoelectric, bioelectronics, drug delivery, retina, sclera, biomaterials, energy harvesting, contact lenses, neuromodulation