Triboelectric nanogenerators (TENGs) have attracted much interest in recent years, due to its effectiveness and low cost for converting high-entropy mechanical energy into electric power. The traditional TENGs generate an alternating current, which requires a rectifier to provide a direct-current (DC) power supply. Herein, a dynamic p-n junction based direct-current triboelectric nanogenerator (DTENG) is demonstrated. When a p-Si wafer is sliding on a n-GaN wafer, carriers are generated at the interface and a DC current is produced along the direction of the built-in electric field, which is called the tribovoltatic effect. Simultaneously, an UV light is illuminated on the p-n junction to enhance the output. The results indicate that the current increases 13 times and the voltage increases 4 times under UV light (365 nm, 28 mW/cm 2 ) irradiation. This work demonstrates the coupling between the tribovoltaic effect and the photovoltaic effect in DTENG semiconductors, promoting further development for energy harvesting in mechanical energy and photon energy.

The kernmantle construction, a kind of braiding structure that is characterized by the kern absorbing most of the stress and the mantle protecting the kern, is widely employed in the field of loading and rescue services, but rarely in flexible electronics. Here, a novel kernmantle electronic braid (E‐braid) for high‐impact sports monitoring, is proposed. The as‐fabricated E‐braids not only demonstrate high strength (31 Mpa), customized elasticity, and nice machine washability (>500 washes) but also exhibit excellent electrical stability (>200 000 cycles) during stretching. For demonstration, the E‐braids are mounted to different parts of the trampoline for athletes’ locomotor behavior monitoring. Furthermore, the E‐braids are proved to act as multifarious intelligent sports gear or wearable equipment such as electronic jump rope and respiration monitoring belt. This study expands the kernmantle structure to soft flexible electronics and then accelerates the development of quantitative analysis in modern sports industry and athletes’ healthcare.

In addition to electrical, optical, and magnetic fields, mechanical forces have demonstrated a strong ability to modulate semiconductor devices. With the rapid development of piezotronics and flexotronics, force regulation has been widely used in field-effect transistors (FETs), human-machine interfaces, light-emitting diodes (LEDs), solar cells, etc. Here, a large mechanical modulation of electronic properties by nano-Newton force in semiconductor materials with a large Young's modulus-based force FET is reported. More importantly, this FET has ultralow switching energy dissipation (7 aJ per decuple current gain) and nearly zero leakage power; these values are even better than those of electronic FETs. This finding paves the way for practical applications of nanoforce modulation devices at high power efficiency.

It is extraordinarily challenging to implement adaptive and seamless interactions between mechanical triggering and current silicon technology for tunable electronics, human-machine interfaces, and micro/nanoelectromechanical systems. Here, we report Si flexoelectronic transistors (SFTs) that can innovatively convert applied mechanical actuations into electrical control signals and achieve directly electromechanical function. Using the strain gradient–induced flexoelectric polarization field in Si as a “gate,” the metal-semiconductor interfacial Schottky barriers’ heights and the channel width of SFT can be substantially modulated, resulting in tunable electronic transports with specific characteristics. Such SFTs and corresponding perception system can not only create a high strain sensitivity but also identify where the mechanical force is applied. These findings provide an in-depth understanding about the mechanism of interface gating and channel width gating in flexoelectronics and develop highly sensitive silicon-based strain sensors, which has great potential to construct the next-generation silicon electromechanical nanodevices and nanosystems.

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The phase transition of SrCoO2.5 (BM-SCO) is very popular in recent reports based on its special structure. The oxygen vacancy channel of BM-SCO provides a convenient condition for phase transformation to SrCoO3‑δ (PV-SCO), with prospects in smart windows, memristive devices, and magnetic recording. The traditional method for phase transition is thermal annealing, while the electric-field-controlled ionic liquid (IL) gating is also a convenient method. Herein, we use a triboelectric nanogenerator as a self-powered system, which can provide a constant voltage for the IL and achieve ion injection to induce phase transition, and this procedure proved to be reversible. X-ray diffraction scanning and high-resolution transmission electron microscope observation showed that the crystal structures of the two phases are significantly different. Besides, BM-SCO is antiferromagnetic, PV-SCO is ferromagnetic, and the optical transmittance also changes during the phase transition. As for the applications of this film, we used IL gating to modulate the resistive switching behavior, which shows a change between high-resistance state and low-resistance state during the phase transition and can be used in resistive random access memory devices.