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Abstract Abnormal vibration is a direct response to the mechanical defects of electrical equipment, and requires reliable vibration sensing for health condition evaluation in the associated system. The triboelectric nanogenerator (TENG) triggered by random vibration to generate electrical energy/signal while giving feedback on the vibration state, paving a promising way towards self‐powered sensors. Here, an all‐in‐one sensing system configured with a vibration sensor demonstrates instantaneous discharge boosted TENG and IR wireless communication for vibration state online monitoring. The sandwich‐structured TENG combined with mechanical switches can release the co‐accumulated charges from dual triboelectric layers to yield giant instantaneous output power of 616 W, which is 10 6 times higher than that of the continuous discharge. Moreover, an IR LED as a transmitter driven by the TENG can form an all‐in‐one vibration sensor enabling wireless communication, where the sensor can be further integrated with repeaters and phones to establish a wireless vibration online monitoring system for vibration state visualization. This work presents a novel idea to implement high‐power TENG with IR communication integration for in situ vibration online monitoring. Such a strategy is potentially available for distributed sensor construction towards abnormal signal monitoring that reflects the operating state of equipment.

No abstract is provided for this article.

Abstract Energy harvesting system based on triboelectric nanogenerators (TENGs) has aroused wide interest from many researchers since it integrates multiple disciplines together including electromagnetics, electric circuit theory, materials science and mechanical engineering. Accurate modeling of a TENG is an indispensable part for revealing the relationships and interactions among physical quantities from different areas. Here, a three-dimensional mathematical model of a contact-mode freestanding TENGs (CF-TENGs) is built with a combination of physical abstraction and geometry configuration, which makes it possible to dynamically analyze the variations of the field and circuit quantities. An accurate Norton’s equivalent circuit model that consists of a current source in parallel with a pure capacitive reactance is proposed. Based on this model the reason for identifying the displacement current as the driving force of TENGs is elucidated, and quantitatively determine the current flowing through the external load resistor and the internal equivalent capacitor. More importantly, a universal dynamic simulation model consisting of a quasi-electrostatic model and a circuit model for the TENG-based energy harvesting system is presented. The presented composite model exhibits an obvious advantage in terms of revealing the dynamic output of TENGs with arbitrary geometry and charge distribution. Finally, based on the characteristics of linearity and time-invariance of the CF-TENG, general optimization strategies are pinpointed, which allow us to accurately predict the maximum output efficiency (close to 82.5%).

Mechanical stimuli have been shown to dynamically alter solid-liquid interfaces and induce electron transfer, enabling catalytic reactions, most notably contact-electro-catalysis (CEC). However, the underlying mechanism of charge transfer at solid-liquid interfaces under mechanical stimulation remains unclear, particularly at semiconductor-liquid interfaces. To date, rare studies have reported on the catalytic activity of semiconductor-liquid interfaces under mechanical stimulation. In this work, we discovered that hydrogen-treated gallium nitride (GaN), which appears gray in optical images, exhibits catalytic activity for hydrogen peroxide generation, whereas conventional yellow GaN shows no catalytic effect under the same conditions. Through material characterization, mechanistic analysis, and density functional theory (DFT) simulations, we unveil the charge transfer dynamics and catalytic mechanism at semiconductor-liquid interface. We found that the nonuniform structure formed during hydrogen treatment, which contributes to the gray color, also plays a crucial role in the catalytic process. Under mechanical stimuli-induced oxygen concentration fluctuations, this interface becomes polarized, creating conditions conducive to electron transfer and sustaining the full hydrogen peroxide reaction cycle. This work provides fundamental insights into mechanically driven semiconductor-based catalysis at semiconductor-liquid interface and contributes to the development of strategies for sustainable energy conversion.

A nanoscale semiconducting ZnO based biosensor with integrated microfluidics is designed, fabricated and tested to demonstrate the detection of streptavidin, a commonly used protein. Amperometric (I-t) measurement is utilized to detect the change of conductivity over time. By comparing with the control experiment, the specific binding event between biotin and streptavidin is detected. The data indicates a conductivity change by more than 20% after the protein hybridization. The second part of the papers presents a ZnO thin film based biosensor which is integated with a microfluidic system. Same experiment protocols are carried and similar change in I-t characteristics is observed. This is the first demonstration of real time biosensing with ZnO nanowires and thin films that are integrated with microfluidic systems. This can be further extended to fabricate bio-sensors which can potentially detect any protein in real time. Amperometric sensing results in a label-free detection system as it detects the protein hybridization events electrically. when integrated on the system-on-package (SOP) platform, this technology can lead to portable, reliable and cost effective biosensors with applications in many areas.

We report the first self-powered electronic skin that consists of light-emitting diode (LED) and triboelectric nanogenerator (TENG) arrays that can be utilized for spatially mapping applied instantaneous-touch events and tracking the movement location of the target object by recording the electroluminescent signals of the LEDs without external power sources. The electret film-based TENG can deliver an open-circuit voltage of about −1070 V, a short-circuit current density of 10 mA/m2, and a power density of 288 mW/m2 on an external load of 100 MΩ. The LEDs can be turned on locally when the back surface of the active matrix is touched, and the intensity of the emitted light depends on the magnitude of the applied local pressure on the device. A constructed active matrix of the LED-TENG array (8 × 7 pixels) can achieve self-powered, visual, and high-resolution tactile sensing by recording the electroluminescent signals from all of the pixels, where the active size of each pixel can be decreased to 10 mm2. This work is a significant step forward in self-powered tactile-mapping visualization technology, with a wide range of potential applications in touchpad technology, personal signatures, smart wallpapers, robotics, and safety-monitoring devices.

No abstract is provided for this article.

BaTiO3 thin films were grown epitaxially on (100) MgO substrates by metalorganic chemical vapor deposition (MOCVD) at a temperature of 600 °C. This substrate temperature is the lowest reported temperature for the growth of epitaxial BaTiO3 films by an MOCVD process. The films had a cube–cube orientation relationship with the substrate and were oriented with an a-axis perpendicular to the substrate plane. Nanoscale energy dispersive x-ray spectrometry measurements showed no evidence of interdiffusion between the film and substrate.

Silicon-based photodetectors in photoelectric sensing applications are crucial. In the previous studies of the piezo-phototronic effect on performance modulation of Si/ZnO heterojunctions, the majority is based on a rigid silicon substrate and a ZnO one-dimensional nanostructure, causing incompatibility with advanced semiconductor processing technology as well as the limitation in the field of wearable application. Here, flexible p-Si/n-ZnO film heterojunction photodetectors have been constructed by sputtering ZnO films on chemically thinned Si substrates. Under 405 nm light illumination and at −0.5 V bias, the reverse photocurrent of the heterojunction under the −0.73‰ compression strain increased by 50.36% compared to that under a strain-free state, while the reverse photocurrent for the same device under 0.73‰ tensile strain decreased by 29.2% compared to that under the strain-free state. The introduction of a flexible silicon wafer realizes a bidirectional photocurrent response regulation, which lies in the fact that the strain-induced piezo-potential governs the local energy band structure at the heterojunction interface and, thus, influences the carrier transport in the heterojunction region. The COMSOL simulation results further verify the evolution of the energy band structure at the heterojunction interface at different strain states. This work provides a strategy to design silicon-based optoelectronic devices via the piezo-phototronic effect of a ZnO film.

ADVERTISEMENT RETURN TO ISSUEPREVAddition/CorrectionORIGINAL ARTICLEThis notice is a correctionOptimizing the Power Output of a ZnO Photocell by PiezopotentialYoufan Hu, Yan Zhang, Yanling Chang, Robert L. Snyder, and Zhong Lin Wang*Cite this: ACS Nano 2010, 4, 8, 4962Publication Date (Web):July 19, 2010Publication History Accepted15 July 2010Published online19 July 2010Published inissue 24 August 2010https://doi.org/10.1021/nn101631vCopyright © 2010 American Chemical SocietyRIGHTS & PERMISSIONSArticle Views571Altmetric-Citations4LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (56 KB) Get e-AlertscloseSUBJECTS:Oxides,Power Get e-Alerts

Turbulence-induced vibrations pose substantial risks to aircraft structural integrity and flight stability, particularly in unmanned aerial vehicles (UAVs), where real-time impact monitoring and lightweight protection are critical. Here, we present a bioinspired twist-hyperbolic metamaterial (THM) integrated with a triboelectric nanogenerator (TENG) for simultaneously impact buffering and self-powered sensing. The THM-TENG protector exhibits tunable stiffness (40 to 4300 newtons per millimeter), ~70% impact energy absorption, and achieves a specific energy absorption of ~0.25 joules per gram at a weight of only 10 grams. Through triboelectrification, the protector converts mechanical energy into electrical signals, enabling real-time monitoring of impact loads up to 1000 newtons (≤5 hertz). Integrated with a microcontroller unit, wireless transmission, and alarm systems, THM-TENG demonstrates dual functionality in UAVs: mitigating vibration while providing real-time force monitoring, positioning, and early warning, all without external power sources. This work establishes a transformative framework for lightweight, multifunctional protective systems with applications in aerospace, robotics, and autonomous vehicles.