Publications

Nondestructive, high-efficiency, and on-demand intracellular drug/biomacromolecule delivery for therapeutic purposes remains a great challenge. Herein, a biomechanical-energy-powered triboelectric nanogenerator (TENG)-driven electroporation system is developed for intracellular drug delivery with high efficiency and minimal cell damage in vitro and in vivo. In the integrated system, a self-powered TENG as a stable voltage pulse source triggers the increase of plasma membrane potential and membrane permeability. Cooperatively, the silicon nanoneedle-array electrode minimizes cellular damage during electroporation via enhancing the localized electrical field at the nanoneedle-cell interface and also decreases plasma membrane fluidity for the enhancement of molecular influx. The integrated system achieves efficient delivery of exogenous materials (small molecules, macromolecules, and siRNA) into different types of cells, including hard-to-transfect primary cells, with delivery efficiency up to 90% and cell viability over 94%. Through simple finger friction or hand slapping of the wearable TENGs, it successfully realizes a transdermal biomolecule delivery with an over threefold depth enhancement in mice. This integrated and self-powered system for active electroporation drug delivery shows great prospect for self-tuning drug delivery and wearable medicine.

Power generation from human sweat has attracted great attention due to its potential application in waste energy scavenging. However, the development of methods to generate sufficient electricity from sweat to power electronic devices for health monitoring remains a major challenge. Here, we report a wearable sweat-based electricity generator (SEG), in which the power generation mechanism is based on the redox reaction between sweat and electrodes. Due to the increase in oxygen adsorption, both the output current and power of SEG with single-walled carbon nanotubes modified electrode can be remarkably enhanced by 5.6 and 14.7 times compared to SEG with a nanotube-free electrode, respectively. The SEGs have been first utilized to power a wireless heart-rate sensor for sustainably transmitting heart-rate data to a smart phone. Moreover, self-powered sensing of lactic acid has been achieved by electric signals with the current sensitivity of 11.79 mmol·L–1·mA–1, demonstrating applications in human health care.

Triboelectric nanogenerators (TENGs) offer great opportunities to deploy advanced wearable electronics that integrate a power generator and smart sensor, which eliminates the associated cost and sustainability concerns. Here, an embodiment of such integrated platforms has been presented in a graphene oxide (GO) based single-electrode TENG (S-TENG). The as-designed multifunctional device could not only harvest tiny bits of mechanical energy from ambient movements with a high power density of 3.13 W·m-2 but also enable detecting dynamic force with an excellent sensitivity of about 388 μA·MPa-1. Because of the two-dimensional nanostructure and excellent surface properties, the GO-based S-TENG shows sensitive force detection and sound antimicrobial activity in comparison with conventional poly(tetrafluoroethylene) (PTFE) electrodes. This technology offers great applicability prospects in portable/wearable electronics, micro/nanoelectromechanical devices, and self-powered sensors.

Abstract Harvesting mechanical energy through triboelectric nanogenerators (TENGs) for effectively purifying water, self‐powered wastewater treatment system presents a promising solution to address both energy and environmental crises. However, issues such as side‐discharge and wear, resulting from interfacial charge transfer, seriously hinder the output and durability of TENGs, and then reduce the efficiency of self‐powered wastewater treatment. Here, an interface charge regulation technique is introduced that simultaneously boosts both output performance and durability of TENG, enabling a greater efficiency in self‐powered wastewater treatment. The interface charge regulation method, suppressing side‐discharge around electrodes with an innovative insulator design as well as boosting charge density through secondary collection, fully utilizes surface charges for power output and results in minimum wear by reducing the interface electrostatic force. Surface charge density of 0.8 mC m −2 between the Ethyl tetrafluoro ethylene and copper ( µ = 0.35), with a threefold enhancement under ambient conditions, and durability of 500 000 cycles (a 12.5‐fold enhancement) are achieved. Furthermore, the removal efficiency for proposed self‐powered sewage filter system is improved onefold, indicating the potential for sustainable and practical applications.

A microfiber‐nanowire hybrid structure is the fundamental component for a wearable piezoelectric nanogenerator (PENG) for harvesting body motion energy. Here, a novel approach combining surface coating and plasma etching techniques is reported to enhance the mechanical reliability of Kevlar microfiber‐ZnO nanowires (NWs) hybrid structure that is used for PENG. After treatment, the hybrid structure has dramatically improved high flexibility, robustness, and durability. On the basis of the coupled piezoelectric and semiconducting properties of ZnO, the processed Kevlar fibers covered with ZnO NWs are utilized to fabricate a 2D nanogenerator (2DNG). The open‐circuit voltage and short‐circuit current of the 2DNG are 1.8 mV and 4.8 pA, respectively. Furthermore, the 2DNG is successfully employed to quantitatively detect UV intensity from 0.2 to 1 mW cm −2 as a self‐powered system.

Abstract For large-aperture dielectric film optics, the uniformity of film refractive index across the aperture is crucial to the uniformity of reflectance and transmittance. Herein, a comparative research has been performed on the refractive index uniformity of HfO 2 films across the Φ560 mm-aperture sample holder for inclined suspension and horizontal suspension. It’s revealed that the refractive index of HfO2 film at edge position of sample holder increased about 1.52% compared to that of HfO2 film at center position for inclined suspension, while the refractive index varied only about 0.25% for horizontal suspension. The further analysis performed on film crystallization, morphology and microstructure show that the large variation of refractive index between the films at center and edge positions of inclined suspension sample holder was attributed to the different growth properties. The film at the edge crystallized more slightly and was denser, thus being of higher refractive index. And the different growth properties of the two films at center and edge positions can be explained in the light of the co-effects of atomic shadowing, reemission and diffusion of ad-atoms during film growth.

In article number 2101147, Linhong Ji, Zhong Lin Wang, Jia Cheng and co-workers develop a novel sliding charge pumping technology which utilizes the unfixed charges shuttling between a triboelectric nanogenerator (TENG) and a commercial capacitor to generate electricity. This stabilizes the voltage and boosts the current of the TENG. The triboelectrification and pumping charges cooperatively elevate its surface charge density, contributing to enhancing the output performance of the TENG.

Wearable electronics containing different functional sensors with abilities to meet people's daily needs are highly desirable. Here, a stretchable triboelectric nanogenerator (TENG) for wearable electronics is demonstrated. By stacking two layers of silicone rubbers embedded with silver nanowires (AgNWs) and a Ni foam as electrodes, respectively, the fabricated TENG can serve as a new type of sensor that is wearable, stretchable, skin-friendly, noninvasive, and durable. It can convert mechanical deformation into electric signals. Deformation like stretching and extruding of the TENG results in interlayer rubbing because of inhomogeneous strain, producing triboelectric charges that can induce voltage signals in the electrodes in response to the deformation. On the basis of the principle, a joint sensor based on the TENG is demonstrated, which can generate different output voltages according to the bending degrees of the joint. Furthermore, a three-dimensional sensor integrating three TENGs is fabricated to depict the deformations of different muscle areas. The output voltages of the three TENGs can be simultaneously monitored to reflect the deformation degrees of different muscle areas.

Abstract In this article, a cylindrical direct‐current triboelectric nanogenerator (DC‐TENG) that can generate an almost constant current output with a low crest factor by phase coupling is reported for the first time. Here, the influence of phases (P) and groups (G) on the DC‐TENG is investigated. Experiments show that the crest factor of current, significantly decreases as the phases increase, and the output performance significantly increases as the groups increase. One phase triboelectric power‐generating unit of the DC‐TENG with three‐phase and five‐group (3P5G) produces an open‐circuit voltage of 149.5 V, short‐circuit current 7.3 μA, and transferred charge of 56.7 nC at 600 rpm. The DC‐TENG can produce a coupling current of 21.6 μA and the average output power of 2.04 mW after each phase output is rectified and superimposed. Additionally, the crest factor of output current is reduced to 1.08, and the high‐performance characteristics of an almost constant direct‐current is achieved. The research is of considerable significance to the practical applications of TENGs in powering sensors of low consumption.

A rotating-disk-based hybridized electromagnetic–triboelectric nanogenerator exhibits a much better charging performance and provides a better platform for WPT.

Abstract Improving the safety and usability of the blind movement is of great significance. The blind navigation system has always been the focus of attention. However, achieving an unconscious interaction and long‐term operation with high navigation accuracy is an urgent challenge. In this study, a distributed self‐powered intelligent voice navigation tactile pavement (SVP) based on a hybrid nanogenerator for blind navigation is reported. More than 4‐s effective output time is achieved under a single instantaneous pressure to the hybrid nanogenerator. The system is integrated with an inertial storage hybrid nanogenerator (ISNG), RF transmitter module, and voice broadcast module. It has the advantages of outstanding navigation accuracy, fatigue resistance (16 000 cycles), temperature stability (−50 to 50 °C), no required operation, and easy fabrication. The SVP may solve the difficulties of GPS navigation delay and lack of map information and realize the accurate identification and feedback of key locations, providing an effective and unconscious interaction navigation strategy for the blind. Integrating the hybrid nanogenerator under the road can provide an energy supply for the construction of the Internet of Things and smart city in the future.