High Energy Density Non‐Contact Bidirectional Spinning Oscillating Float‐Type Triboelectric Nanogenerators for Energy Extraction From Irregular Waves

The pursuit of sustainable and self-sufficient energy solutions has become critical for the advancement of marine IoT technologies. Here, by utilizing the vertical energy transformation mechanism design, a novel non-contact bidirectional spinning oscillating float-type triboelectric nanogenerator is presented for capturing random and multi-directional wave energy. Furthermore, an intelligent self-powered marine ranching system for automatic feeding and water quality monitoring is developed.

Abstract

The pursuit of sustainable and self-sufficient energy solutions has become critical for the advancement of marine Internet of Things (IoT) technologies. While triboelectric nanogenerators (TENGs) have shown great potential in harnessing high-entropy, low-frequency wave energy, their practical applications are hindered by low power output and issues related to frictional wear. Hence, this research presents a novel non-contact bidirectional spinning oscillating float-type triboelectric nanogenerator (OF-TENG) for efficient wave energy harvesting. Utilizing a planetary gear and bidirectional rotation structural design, low-frequency vertical wave energy with random and multi-directional conditions can be converted into high-frequency rotational energy. At a frequency of 0.5 Hz, the OF-TENG achieves a peak output power of 93.48 mW, and an average output volumetric power density of 31.3 W m⁻³. Furthermore, the non-contact working mode ensures robust output stability, with no significant performance degradation observed after 5,680,000 working cycles. An intelligent self-powered marine ranching system for automatic feeding and water quality monitoring is further developed based on the OF-TENG. This work not only provides an effective solution for harvesting low-frequency wave energy, but also promotes the development of smart marine IoT technologies and marine agriculture.