Publications

An epidemic of low quality medicines continues to endanger patients worldwide. Detection of such "medicines" requires low cost, ambient ionization sources coupled to fieldable mass spectrometers for optimum sensitivity and specificity. With the use of triboelectric nanogenerators (TENGs), the charge required to produce gas-phase ions for mass analysis can be obtained without the need for high voltage electrical circuitry, simplifying and lowering the cost of next-generation mass spectrometry instruments.

Abstract The use of water resources for energy generation has become increasingly prevalent, encompassing the conversion of kinetic energy from streams, tides, and waves into renewable electrical power. Water energy sources offer numerous benefits, including widespread availability, stability, and the absence of carbon dioxide and other greenhouse gas emissions, making them a clean and environmentally friendly form of energy. In this work, we develop a droplet-based liquid–solid triboelectric nanogenerator (LS-TENG) using sophisticatedly designed inflatable columnar structures with inner and outer dual-electrodes. This device can be utilized to harvest both the internal droplet-rolling mechanical energy and the external droplet-falling mechanical energy, capable of being assembled into various structures for versatile applications. The design incorporates a combined structure of both internal and external TENG to optimize output performance via multiple energy harvesting strategies. The internal structure features a dual-electrode columnar-shaped LS-TENG, designed to harvest fluid kinetic energy from water droplets. By leveraging the back-and-forth motion of a small amount of water within the air column, mechanical energy can be readily collected, achieving a maximum mass power density of 9.02 W·Kg −1 and an energy conversion efficiency of 10.358%. The external component is a droplet-based LS-TENG, which utilizes a double-layer capacitor switch effect elucidated with an equivalent circuit model. Remarkably, without the need for pre-charging, a single droplet can generate over 140 V of high voltage, achieving a maximum power density of 7.35 W·m −2 and an energy conversion efficiency of 22.058%. The combined LS-TENG with a sophisticated inflatable columnar structure can simultaneously collect multiple types of energy with high efficacy, exhibiting great significance in potential applications such as TENG aeration rollers, inflatable lifejacket, wind energy harvesting, TENG tents, and green houses.

Abstract As a microenergy harvesting device, the output performance of triboelectric nanogenerators (TENGs) has long been limited by their surface charges. In this work, an enhancement of the output performance of TENGs via charge clamping (CC‐TENG) is proposed. The device is comprised of a mechanical‐switch direct‐current TENG (MDC‐TENG), charge clamping module (CCM), and main‐TENG. During operation, the CCM is employed to accumulate and clamp the unidirectional charge generated by the MDC‐TENG. And then, the accumulated charges flow between CCM and main‐TENG. With the increase of transferred charges, the output performance can be effectively improved. In addition, the MDC‐TENG is employed to reduce both power dissipation and circuit complexity. Furthermore, an integrated device based on the CC‐TENG is demonstrated which harvests wind energy and attains a charge output of 1.01 µ C. Moreover, a multimode coupling is adopted, that is, an alternating‐current TENG operating in contact‐separation mode and a direct‐current TENG operating in a lateral‐sliding mode that can be employed in environments for which multiple motions coexist. The device provides a reference to improve output performance in the context of wind energy capture.

Harvesting biomechanical energy is an important route for providing electricity to sustainably drive wearable electronics, which currently still use batteries and therefore need to be charged or replaced/disposed frequently. Here we report an approach that can continuously power wearable electronics only by human motion, realized through a triboelectric nanogenerator (TENG) with optimized materials and structural design. Fabricated by elastomeric materials and a helix inner electrode sticking on a tube with the dielectric layer and outer electrode, the TENG has desirable features including flexibility, stretchability, isotropy, weavability, water-resistance and a high surface charge density of 250 μC m-2. With only the energy extracted from walking or jogging by the TENG that is built in outsoles, wearable electronics such as an electronic watch and fitness tracker can be immediately and continuously powered.

Abstract Electromagnetic radiation, as one of the public hazards that injures human health and information safety, shall be shielded from the ambient environment. Here, by the virtue of polypyrrole polymerized polyamide yarns and silicone rubber, a yarn‐based electromagnetic shielding‐triboelectric nanogenerator (EMS‐TENG) equipped with sensing ability is presented, which not only generates electricity from harvesting body motion energy but also serves as EMS to prevent electromagnetic interference. With the aid of knitting method, the developed EMS‐TENG fabric exhibits the EMS effectiveness of 32.49 dB in 8.2–12.5 GHz and achieves a maximum instantaneous peak power density of 142.27 µW m −1 . Furthermore, a real‐time human‐interactive system is developed by adopting the Internet of Things technology and EMS‐TENG sensor. Based on the above, a simulated intelligent calculator with multiplication and division function is proposed, which can successfully translate electronic signals to digital numbers. With energy harvesting and self‐powered sensing abilities, the EMS‐TENG can convert mechanical energy into electrical signals from human movements. Looking forward, the EMS‐TENG spurs an innovative technique toward a self‐powered human‐interactive sensing and functional protective textile for next‐generation intelligent wearable applications.

Overpressure measurement is an important approach to evaluate the power of shock wave (SW) monitoring. Traditional wired monitoring systems exhibit the limitations of high-cost, heavyweight, troublesome maintenance, and big-data transmission in SW monitoring. In this article, a new lightweight FPGA-based wireless overpressure node (LFWON) with the resistance to high-temperature and high-pressure environment for SW monitoring. The proposed LFWON is based on the Spartan-6 XC6SLX92TQG144C FPGA circuit, via a serial peripheral interface to the RF transceiver and data bus to the NAND flash chip for data management. To validate the LFWON, experimental tests in terms of dynamic parameters and network quality are performed in a real blast testing with 8-kg trinitrotoluene. This article is conducted to provide new insights into how the antishocking structure and sensing algorithm of wireless sensor node is designed in SW monitoring for acquiring overpressure accurately. The results show that the errors of ΔP(7 m-12 m), t <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">d</sub> (>6 m), and I <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">+</sup> (3 m-24 m) from proposed LFWON are below 20% in comparison with wired system. In addition, the RSSI value of LFWON should be set above -70 dBm for stable communication quality.

Abstract Developing energy harvesting devices is crucial to mitigate the dependence on conventional and rigid batteries in wearable electronics, ensuring their autonomous operation. Nanogenerators offer a cost‐effective solution for enabling continuous operation of wearable electronics. Herein, this study proposes a novel strategy that combines freeze‐casting, freeze‐drying, and printing technologies to fabricate a fully printed triboelectric nanogenerator (TENG) based on polyvinylidene fluorid‐etrifluoroethylene P(VDF‐TrFE) porous aerogel. First, the effects of porosity and poling on the stretchability and energy harvesting capabilities of P(VDF‐TrFE) are investigated, conducting a comprehensive analysis of this porous structure's impact on the mechanical, ferroelectric, and triboelectric properties compared to solid P(VDF‐TrFE) films. The results demonstrate that structural modification of P(VDF‐TrFE) significantly enhances stretchability increasing it from 7.7% (solid) to 66.4% (porous). This modification enhances output voltage by 66% and generated charges by 48% for non‐poled P(VDF‐TrFE) porous aerogel films compared to their non‐poled solid counterparts. Then, a fully printed TENG is demonstrated using stretchable materials, exhibiting a peak power of 62.8 mW m −2 and an average power of 9.9 mW m −2 over 100 tapping cycles at 0.75 Hz. It can illuminate light‐emitting diodes (LEDs) through the harvesting of mechanical energy from human motion. This study provides a significant advance in the development of energy harvesting devices.

Patients suffering from coronary artery disease (CAD) or peripheral arterial disease (PAD) can benefit from bypass graft surgery. For this surgery, arterial vascular grafts have become promising alternatives when autologous grafts are inaccessible but suffer from numerous postimplantation challenges, particularly delayed endothelialization, intimal hyperplasia, high risk of thrombogenicity and restenosis, and difficulty in timely detection of these subtle pathological changes. We present an electronic vascular conduit that integrates flexible electronics into bionic vascular grafts for in situ, real-time and long-term monitoring for hemadostenosis and thrombosis concurrent with postoperative vascular repair. Following bypass surgery, the integrated bioelectronic sensor based on the triboelectric effect enables monitoring of the blood flow in the vascular graft and identification of lesions in real time for up to three months. In male nonhuman primate cynomolgus monkeys, the electronic vascular conduit, with an integrated wireless signal transmission module, enables wireless and real-time hemodynamic monitoring and timely identification of thrombi. This electronic vascular conduit demonstrates potential as a treatment-monitoring platform, providing a sensitive and intuitive monitoring technique during the critical period after bypass surgery in patients with CAD and PAD. Arterial vascular grafts are promising for vascular reconstruction but face risk of restenosis. Here, the authors report an electronic vascular conduit for in situ, long-term monitoring of thrombosis concurrent with postoperative vascular repair in in small animals and nonhuman primates.