High-sensitivity blue-energy-shuttle and in-situ electrical behaviors in ocean

Although various triboelectric nanogenerators (TENGs) and hybrid ocean kinetic energy harvesters (OKEHs) have been devised for blue energy harvesting, the lack of studies in the real ocean has hindered their progress. Here, a high-sensitivity modular shuttle-like hybrid nanogenerator (MSHG) is prepared, comprising contact-separation TENG, piezoelectric nanogenerator (PENG), and electromagnetic generator (EMG) components. Its acceleration feature and electrical performance were systematically investigated under various conditions, from laboratory setups to real ocean waves. The MSHG responds sensitively to low-level excitations and exhibits robust energy harvesting capability in the ocean. Statistical analysis shows that its most probable output frequency reaches 0.83 Hz, which is about four times higher than the main frequency of the ocean wave (0.1-0.2 Hz). A 12-integrated MSHG system effectively harvests ocean wave energy to power a water-quality detector, while its most probable acceleration amplitude is approximately 24% of the maximum in a simulated linear motor motion and 57% of the mean value under simulated water wave. The findings provide valuable insights for advancing nanogenerator applications in real oceans.