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Triboelectric nanogenerator (TENG) is an attractive approach to power wearable electronic devices by harvesting energy from the environment. To further improve the electricity generation efficiency, a honeycomb‐shaped triboelectric nanogenerator (H‐TENG) with high spatial density and extendibility for human kinetic energy harvesting and motion monitoring is proposed. The honeycomb structure enables the H‐TENG to extend and stack along the required direction when in restricted space, which consequently achieves enhancive space utilization and power density promotion. 3D‐printed thermoplastic polyurethane as the elastic shell endows the H‐TENG with robust mechanical flexibility, high deformation, and advantageous fatigue resistance. In the output experiment, H‐TENG exhibits excellent electricity generation performance, that the maximum open‐circuit voltage and power density can reach 1500 V and 10.79 W m−2. In addition, the H‐TENG can not only light 252 white light‐emitting diodes with tapping, power the electronic watch and pedometer with walking, but also can maintain the sustainable running of the electronic thermometer. Moreover, H‐TENG manifests an extraordinary sensible response to the elbow bending of different angles and can estimate the walking speed from the frequency, demonstrating the potential of H‐TENG both as the biomechanical sensor and energy harvester of human movement.

Electrostatic energy-storage capacitors, with their ultrahigh storage density and high temperature stability, have been receiving increasing attention of late for their ability to meet the critical requirements of pulsed power devices in low-consumption systems. In such a context, this work reports on the successful production of anti-ferroelectric (AFE) thin films with excellent energy storage performance under a relatively low electric field. In particular, La-doped PbZrO 3 thin films were fabricated using a sol-gel method, yielding a recoverable energy storage density of 34.87 J cm −3 with an efficiency of 59.23% at room temperature under the electric field of~800 kV cm −1. The temperature dependence of the energy storage property was demonstrated from room temperature to 210°C, indicating a stable density variation between 34.87 and 27.98 J cm −3. The films also exhibited excellent anti-fatigue property (endurance of up to 3×10 9 cycles and the recoverable energy storage density varied from 39.78 to 29.32 J cm −3 combined with an efficiency of 61.03%-44.95% under the test frequencies from 10 to 5000 Hz). All results were obtained using compact films with a high polarization (P max) of approximately 103.7 μC cm −2 and low remnant polarization (P r~7 μC cm −2), which was owing to the combination of LaNiO 3 buffer layers and vacancies at Pb sites. These results illustrate the great potential of pulsed power devices in low-consumption systems operating in a wide range of temperatures and long-term operations.

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