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.

A novel method of fabricating large-scale horizontally aligned ZnO microrod arrays with controlled orientation and periodic distribution via combing technology is introduced. Horizontally aligned ZnO microrod arrays with uniform orientation and periodic distribution can be realized based on the conventional bottom-up method prepared vertically aligned ZnO microrod matrix via the combing method. When the combing parameters are changed, the orientation of horizontally aligned ZnO microrod arrays can be adjusted (θ = 90° or 45°) in a plane and a misalignment angle of the microrods (0.3° to 2.3°) with low-growth density can be obtained. To explore the potential applications based on the vertically and horizontally aligned ZnO microrods on p-GaN layer, piezo-phototronic devices such as heterojunction LEDs are built. Electroluminescence (EL) emission patterns can be adjusted for the vertically and horizontally aligned ZnO microrods/p-GaN heterojunction LEDs by applying forward bias. Moreover, the emission color from UV-blue to yellow-green can be tuned by investigating the piezoelectric properties of the materials. The EL emission mechanisms of the LEDs are discussed in terms of band diagrams of the heterojunctions and carrier recombination processes.

This paper proposes a new model for the longitudinal piezoelectric coefficient (LPC) measurement of the aluminum nitride (AlN) thin film on (100) Si substrate, the AlN thin film is fabricated by the direct-current magnetron sputtering and the piezoelectricity of the AlN thin film is measured by the piezoresponse force microscopy (PFM) in contact mode. In this model, the electric field distribution is taken into account, and the electrostriction displacement caused by the local field concentration is excluded from the measured displacement by the PFM. A LPC value of 4.22 ± 0.34 pm/V is obtained for the clamped AlN thin film by this model, and the deviation between this value and that measured under homogenous field condition is \5.7 %. Therefore, it is reasonable to apply our model to the piezoelectricity characterization of AlN thin films when using the PFM. Furthermore, piezoelectricity of other thin films could also be characterized using this model, which could simplify the measurement process.

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Laser-direct-writing of molecule-like Agmx+ nanoclusters in a developed TeO2–ZnO–Na2O–Ag2O glass with low-melting nature was achieved using a portable low-power miniature desktop laser machine.

Carrier generation, transport, separation, and recombination behaviors can be modulated for improving the performance of semiconductor devices by using piezotronic and piezo-phototronic effects with creating piezopotential in crystals based on non-centrosymmetric semiconductor materials such as group II-VI and III-V semiconductors and transition metal dichalcogenides (TMDCs), which have emerged as attractive materials for electronic/photonic applications because of their novel properties. Until now, much effort has been devoted to improving the performance of devices based on the aforementioned materials through modulation of the carrier behavior. However, due to existing drawbacks, it has been difficult to further enhance the device performance for a built structure. However, effective exploration of the piezotronic and piezophototronic effects in these semiconducting materials could pave the way to the realization of high-performance devices. In general, the effective modulation of carrier behavior dynamically in devices such as light-emitting diodes, photodetectors, solar cells, nanogenerators, and so on, remains a key challenge. Due to the polarization of ions in semiconductor materials with noncentral symmetry under external strain, a piezopotential is created considering piezotronic and piezo-photoronic effects, which could dynamically modulate charge carrier transport behaviors across p-n junctions or metal-semiconductor interfaces. Through a combination of these effects and semiconductor properties, the performance of the related devices could be improved and new types of devices such as piezoelectric field-effect transistors and sensors have emerged, with potential applications in self-driven devices for effective energy harvesting and

No abstract

Metasurface regulates the polarization, phase, amplitude, frequency, and other characteristics of electromagnetic waves through the subwavelength microstructure. By using its polarization characteristics, it can realize the functions of optical rotation and vector beam generation. It is the most widely used method of regulation. However, parallel optical manipulation, imaging, and communication usually require polarization-insensitive focused (or vortex) arrays of beams, so polarization-independent wavelength multiplexing optical systems need to be considered. In this paper, the genetic algorithm combined with the computer-generated hologram (CGH) is used to control the transmission phase of the structure itself, and on the basis of wavelength multiplexing, the corresponding array of focused or vortex beams without the polarization selection property is realized. The simulation software results show that the method has a huge application prospect in optical communication and optical manipulation.