High-performance omnidirectional-sliding hybrid nanogenerator for self-powered wireless nodes

Energy-autonomous smart electronics have been the focus of the next generation of the Internet of Things. Recently, advanced power technology with sustainable energy supply and pollution-free characteristics has become a research hotspot. Herein, to realize a reliable and unattended power unit, we propose a high-performance omnidirectional-sliding triboelectric-electromagnetic hybrid nanogenerator (OS-TEHNG) to convert the mechanical energy into electricity. The free-standing triboelectric nanogenerator (TENG) achieves a charge transfer of 24.4 μC in one cycle and a short-circuit current of 0.36 mA after optimizing the electrode structure. The TENG with 130 kΩ impedance allows efficient charging of energy storage units without complex power management modules (PMMs). The electromagnetic part achieves an open-circuit voltage of 300 V after optimization. OS-TEHNG achieves a peak power density of 1568.4 W/m3 and an average power density of 352.3 W/m3 at 2 Hz. As a result, OS-TEHNG charges a 1 mF capacitor to 46 V within 8 s. The strong power supply capability allows OS-TEHNG to charge smartwatches and phones. Furthermore, a completely self-powered wireless keyboard with a PMM and an energy storage unit based on OS-TEHNG is developed. The wireless self-powered keyboard sends data 213 times after only sliding the OS-TEHNG once. Finally, OS-TEHNG is successfully demonstrated to drive a 40 mW wireless sensor node with a 1.3-inch OLED screen in continuous operation. This work represents a significant advance toward self-powered microsystems and practical power sources.