Publications

Abstract Smart skin is expected to be stretchable and tactile for bionic robots as the medium with the ambient environment. Here, a stretchable triboelectric–photonic smart skin (STPS) is reported that enables multidimensional tactile and gesture sensing for a robotic hand. With a grating‐structured metal film as the bioinspired skin stripe, the STPS exhibits a tunable aggregation‐induced emission in a lateral tensile range of 0–160%. Moreover, the STPS can be used as a triboelectric nanogenerator for vertical pressure sensing with a maximum sensitivity of 34 mV Pa −1 . The pressure sensing characteristics can remain stable in different stretching conditions, which demonstrates a synchronous and independent sensing property for external stimuli with great durability. By integrating on a robotic hand as a conformal covering, the STPS shows multidimensional mechanical sensing abilities for external touch and different gestures with joints bending. This work has first demonstrated a triboelectric–photonic coupled multifunctional sensing terminal, which may have great applications in human–machine interaction, soft robots, and artificial intelligence.

We report a nanowire-based biofuel cell based on a single proton conductive polymer nanowire for converting chemical energy from biofluids, such as glucose/blood, into electricity, with glucose oxidase and laccase as catalyst. The glucose is supplied from the biofluid, the nanowire serves as the proton conductor, and the whole cell can be realized at the nano/micrometer scale. The biofuel cell composed of a single nanowire generates an output power as high as 0.5–3 μW, and it has been integrated with a set of nanowire-based sensors for performing self-powered sensing. This study shows the feasibility of building self-powered nanodevices for the biological sciences, environmental monitoring, defense technology, and even personal electronics.

Abstract not Available.

ZnO nanotetrapods (ZnO NTs) with a non-centrosymmetric crystal structure consisting of four 1-D arms interconnected together through a central crystalline core, introduce interesting piezoelectric semiconducting responses in nanorods in the bent state. Considering the widespread applications of nanotetrapods in semiconductor devices, it becomes very crucial to establish a coupled model based on piezoelectric and piezotronic effects to investigate the carrier transport mechanism, which is being reported here in detail for the first time. In this work, we established a multiphysics coupled model of stress-regulated charge carrier transport by the finite element method (FEM), which considers the full account of the wurtzite (WZ) and zinc blende (ZB) regions as well as the spontaneous polarization dependence and the dependence of the material properties on the arm orientation. It is discovered that the forward gain of ZnO NT in the lateral force working mode is almost 50% higher than that in the nanorod in the normal force working mode while the reverse current is reduced to negligible. Through the simulation calculations and corresponding analysis, it is confirmed that the developed piezoelectric polarization charges are able to regulate the transport and distribution of carriers in ZnO crystal, which lays a theoretical foundation for the application of piezo-semiconductive ZnO NT devices in advanced technologies.

Transition metal dichalcogenides (TMDCs) with 2H phase are expected to be building blocks in next-generation electronics; however, they suffer from electrical anisotropy, which is the basics for multi-terminal artificial synaptic devices, digital inverters, and anisotropic memtransistors, which are highly desired in neuromorphic computing. Herein, the anisotropic carrier mobility from 2H WSe2 is reported, where the anisotropic degree of carrier mobility spans from 0.16 to 0.95 for various WSe2 field-effect transistors under a gate voltage of -60 V. Phonon scattering, impurity ions scattering, and defect scattering are excluded for anisotropic mobility. An intrinsic screening layer is proposed and confirmed by Z-contrast scanning transmission electron microscopy (STEM) imaging to respond to the electrical anisotropy. Seven types of intrinsic screening layers are created and calculated by density functional theory to evaluate the modulated electronic structures, effective masses, and scattering intensities, resulting in anisotropic mobility. The discovery of anisotropic carrier mobility from 2H WSe2 provides a degree of freedom for adjusting the physical properties of 2H TMDCs and fertile ground for exploring and integrating TMDC electronic transistors with better performance along the direction of high mobility.

Abstract Flexible and wearable energy harvesting devices and multifunctional sensors have been widely reported, but challenges in the large‐scale manufacturing process still exist. This work reports a large‐scale fabrication method of core‐shell triboelectric braided fibers that exhibit stable structure and strong tensile strength, which can be further integrated into power textiles with different fabric structures, such as weaving and knitting, with the purpose of biomechanical energy harvesting or plantar pressure monitoring. The triboelectric braided fibers integrating on the knitting power textiles exhibit good pressure sensitivity and fatigue resistance, which is combined with traditional socks to measure the pressure distribution of the plantar in different positions. The weaving power textiles exhibit high electrical output, which can be used for biomechanical energy harvesting and can easily light up 116 commercial LEDs. This large‐scale preparation approach provides more possibilities for power textiles applications in self‐powered wearable electronics and human–computer interfacing.

Abstract Energy harvesters based on tribovoltaic effect are interesting due to their direct current output characteristic that matches most commercial electronic devices. However, their mechanism remains to be further investigated, especially for liquid‐solid cases. Here, the effect of temperature on the tribovoltaic effect at liquid‐solid interfaces is studied. The results show that the increasing of temperature will lead to the increase of the tribo‐voltage and tribo‐current at the water/Si and water/metal interfaces during sliding. Moreover, the coupling effect of the pH value of the liquid and the temperature on the tribovoltaic effect is demonstrated, and an energy band model is proposed for understanding the received data, in which the energy released (“bindington”) by contacting the liquid and the solid with the formation of chemical bonds is considered to be responsible for the generation of tribovoltaic effect.

Gains and phases delay induced by sensor position error would significantly degrade the performance of high-resolution two-dimensional multiple signal classification (2D-MUSIC) algorithm, which resulting in low positioning estimation accuracy and poor imaging. In this study, adaptive piezoelectric sensor array calibration based method is proposed for impact localization on composite structure. First, observed signal vector from the sensor array is represented by error calibration matrix with unknown gains and phases, and then it used to construct the cost function including sensor array parameters. Second, a 2D-MUSIC algorithm based on linear attenuation calibration is applied for estimating the initial estimate of impact location. Finally, substituting the initial estimate, the cost function is minimized by adaptive iterative to calculate the sensor array error parameters and the exact location of the impact source. Both finite element method (FEM) simulation and experimental results on carbon-fiber composite panel demonstrate the validity and effectiveness of the proposed method.

Abstract Multidirectional irregular breaking wave is the most prominent feature of the ocean surface and bears tremendous amounts of sustainable high‐entropy energy. However, the commercial utilization and harvesting efficiency are very limited low due to its low‐frequency and low‐amplitude. Here, a swing self‐regulated triboelectric nanogenerator (SSR‐TENG) is proposed, which can convert collected low‐grade breaking waves energy into electrical energy by regulating the oscillation frequency and resonance effect. Benefiting from simple and efficient structural strategy, SSR‐TENG outputs a peak power of 0.14 mW under wave height range of 6–11 cm, that the open‐circuit voltage, short‐circuit current and transferred charge increases is 5.8, 4, and 3.7 times compared to without self‐regulated design, respectively. This work gives a practical solution to the problems faced by harvesting high‐entropy ocean breaking waves energy, which exhibits large potential for building the self‐powered ocean assessment and meteorology system in the future.