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The precision in controlling fluid flow is crucial for the efficiency of microchannel devices. Consequently, it is essential to monitor the fluid within microchannels in real time. However, the microchannel flow's susceptibility to disturbance and small size present challenges in sensing. A Liquid‐Solid Triboelectric Nanogenerator (TENG) with grating electrodes is proposed for non‐invasive sensing of liquid plug movements in microchannels and is suitable for use with opaque channels. This sensor operates on the principle of initiating multiple pulse signals via grating electrodes. And analyze the motion of the liquid plug by the time difference between the signal peaks. It facilitates the measurement of liquid plug count, average speed, average acceleration, and the detection of flow direction. The liquid plug counters, and flow direction sensors yielded clear and distinguishable signals. The liquid plug average speed sensor achieves a 95% accuracy rate, and the acceleration sensor accurately distinguishes speed trends of the liquid plug with more than 85% precision. Grating electrodes are effectively employed for motion sensing. Analyzing the motion of an object by the time difference between voltage peaks offers greater stability than voltage magnitude analysis. Four portable prototypes are designed to make them applicable for fluid sensing in microchannel devices. [ABSTRACT FROM AUTHOR]

This paper proposes a highly integrated triboelectric‐electromagnetic wave energy harvester (TEWEH) that can efficiently collect wide‐frequency wave energy and realize a self‐powered marine buoy. The innovative design of a permanent magnet‐polytetrafluoroethylene (PM‐PTFE) ball ensures high integration between the magnetic material forming the electromagnetic generator (EMG) and the dielectric material forming the triboelectric nanogenerator (TENG). In the condition of swinging (1 Hz and ±30°), the output of the TENG component can reach 230.25 V, 1.34 µA, and the average output of the EMG is 2.30 V, 10.43 mA. Remarkably, even at an extremely low frequency (0.2 Hz), the TEWEH maintains exceptional output. The output power density of the TENG component and EMG component reach 13.77 W m−3 and 148.24 W m−3, respectively, which are much higher than in previous work. The TEWEH can quickly charge the 330 µF capacitor to a certain voltage, and then light up navigation mark lights and power thermometers. A sealed TEWEH with circuits works as a self‐powered marine buoy that can transmit actual marine ambient temperatures to land. In conclusion, the TEWEH has broad application prospects in the field of wave energy harvesting and the self‐powered marine Internet of Things. [ABSTRACT FROM AUTHOR]

Measurement while drilling (MWD) system of offshore drill pipe is of great significance for safety production. It is greatly demanded to develop a sustainable power supply as well as self‐powered sensors for the MWD system. In this work, a drill pipe‐embedded annular type triboelectric nanogenerator (AT‐TENG) is proposed and systematically investigated, and it consists of an annular silicone rubber and a pair of electrodes. The design of the AT‐TENG allows the silicone rubber to contact and separate with the electrodes easily in a narrow space under arbitrary direction vibration to realize power generation. The experimental results show that the peak power density of AT‐TENG with single‐pair electrode reaches 63.7 W m−3 under the vibration frequency of 4 Hz and amplitude of 100 mm. The minimum peak voltage is >65 V within 360° lateral vibration range. The peak voltage achieves 351.62 V under the third‐order natural frequency. In addition, the amplitude and frequency obtained from the voltage signals exhibit linearly with those of actual vibration. The mean error between the frequency detected by AT‐TENG and actual frequency is <0.03%. Thus, the AT‐TENG can serve as an energy harvester and self‐powered vibration sensor. [ABSTRACT FROM AUTHOR]