Passive Wireless Marine Internet-of-Things Buoy Based on Hybrid Nanogenerator with Omnidirectional Water-Wave Energy Harvesting

Efficient harvesting of directional uncertain wave energy by constructing omnidirectional, anti-capsize and high-output floating wave energy harvesting device is the cornerstone of developing passive wireless Marine Internet-of-Things (MIoT) buoy. However, the current research on water-wave energy harvesting is difficult to take into account the above requirements. Herein, we developed a triboelectric-electromagnetic hybrid nanogenerator buoy with the omnidirectional water-wave efficient harvesting by using the integrated structural design. By using the large-weight coil and magnet of electromagnetic generator (EMG) to construct the tumbler and the simple pendulum structure, the water-wave power capture was greatly improved. Furthermore, combined with the light-weight triboelectric nanogenerator (TENG), the floating and anti-overturning performance of device were significantly enhanced. Importantly, by optimizing the structure of TENG and EMG, the output performance of the whole device was improved. Finally, an in-situ power supply with stable voltage output is constructed by integrating energy storage device and voltage regulator circuit, as well as a passive wireless MIoT buoy with real-time sensing signal transmission is constructed by combining sensing and wireless signal transmission modules. Our findings not only provide important technical support for the efficient development of water-wave energy and the development of smart MIoT buoys.