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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.

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.

Flexible electronic technology has attracted great attention due to its wide range of potential applications in the fields of healthcare, robotics, and artificial intelligence, etc. In this work, we have successfully fabricated flexible AlGaN/GaN high-electron-mobility transistors (HEMTs) arrays through a low-damage and wafer-scale substrate transfer technology from a rigid Si substrate. The flexible AlGaN/GaN HEMTs have excellent electrical performances with the Id,max achieving 290 mA/mm at Vgs = +2 V and the gm,max reaching to 40 mS/mm. The piezotronic effect provides a different freedom to optimize device performances, and flexible HEMTs can endure the larger mechanical distortions. Based on the piezotronic effect, we applied an external stress to significantly modulate the electrical performances of flexible HEMTs. The piezotronic effect modulated flexible AlGaN/GaN HEMTs exhibit great potential in human-machine interface, intelligent microinductor systems, and active sensors, etc, and introduce an opportunity to sensing or feedback external mechanical stimuli and so on.

Abstract Although dielectric elastomer actuators (DEAs) are promising artificial muscles for use as visual prostheses in patients with oculomotor nerve palsy (ONP), high driving voltage coupled with vulnerable compliant electrodes limits their safe long‐term service. Herein, a self‐healable polydimethylsiloxane compliant electrode based on reversible imine bonds and hydrogen bonds is prepared and coated on an acrylic ester film to develop a self‐healable DEA (SDEA), followed by actuation with a high‐output triboelectric nanogenerator (TENG) to construct a self‐powered DEA (TENG‐SDEA). Under 135.9 kV mm −1 , the SDEA exhibits an elevated actuated strain of 50.6%, comparable to the actuation under DC power. Moreover, the mechanically damaged TENG‐SDEA displays a self‐healing efficiency of over 90% for 10 cycles. The TENG ensures the safe using of TENG‐SDEAs and an extraocular‐muscle‐like actuator with oriented motion ability integrated by several TENG‐SDEAs is constructed. Additionally, the SDEA is directly used as a flexible capacitive sensor for real‐time monitoring of the patient's muscle movement. Accordingly, a medical aid system based on a conjunction of the extraocular‐muscle‐like actuator and a flexible capacitive sensor is manufactured to help the patients suffering from ONP with physical rehabilitation and treatment.

We report a hybridized nanogenerator with dimensions of 6.7 cm × 4.5 cm × 2 cm and a weight of 42.3 g that consists of two triboelectric nanogenerators (TENGs) and two electromagnetic generators (EMGs) for scavenging air-flow energy. Under an air-flow speed of about 18 m/s, the hybridized nanogenerator can deliver largest output powers of 3.5 mW for one TENG (in correspondence of power per unit mass/volume: 8.8 mW/g and 14.6 kW/m3) at a loading resistance of 3 MΩ and 1.8 mW for one EMG (in correspondence of power per unit mass/volume: 0.3 mW/g and 0.4 kW/m3) at a loading resistance of 2 kΩ, respectively. The hybridized nanogenerator can be utilized to charge a capacitor of 3300 μF to sustainably power four temperature sensors for realizing self-powered temperature sensor networks. Moreover, a wireless temperature sensor driven by a hybridized nanogenerator charged Li-ion battery can work well to send the temperature data to a receiver/computer at a distance of 1.5 m. This work takes a significant step toward air-flow energy harvesting and its potential applications in self-powered wireless sensor networks.

Harvesting mechanical energy via a triboelectric nanogenerator (TENG) is a promising strategy for solving energy problems. However, it is necessary to develop an effective and safe energy managing circuit for preventing high voltage breaking electronic devices. Here, a universal managing circuit is developed to optimize TENG's output performance, which for the first time allows the TENG to safely power various sensor systems with a safe and stable voltage. Based on the circuit, TENG's output can be transformed into a stable voltage with tunable amplitude, while an enhanced short-circuit current of 94 mA with an energy loss lower than 5% is achieved. For demonstrations, three different types of TENGs, respectively, targeting at ocean energy, wind energy, and walking energy have been prepared to reveal the capability of the circuit. This study offers a strategy to greatly enhance the output performance of TENGs to provide useful guidance for constructing self-powered and distributed sensor systems.

Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.