Hybridized nanogenerator based on honeycomb-like three electrodes for efficient ocean wave energy harvesting

Ocean energy is one of the most promising clean and renewable natural energy sources, however, owing to traditional energy harvesting technology, the collection and utilization of ocean energy is extremely limited. In this work, a hybridized ocean wave nanogenerator (How-NG) based on honeycomb-like three electrodes has been proposed, which consists of a triboelectric nanogenerator (TENG) and an electromagnetic generator (EMG), where the TENG works in both in-plane sliding mode and vertical contact-separation mode. With innovative design in electrode structure and hybrid of TENG and EMG, the How-NG can harvest two types of wave energy, kinetic energy and potential energy of ocean surface wave. The honeycomb-like three electrode structure is designed to harvest wave energy in multi-angle range for random waves. In addition, by adjusting the weight of the magnet to achieve different resonance parameters, the How-NG could reach a resonant state and more efficient collection of ocean energy. Furthermore, the influence of the working frequency and sliding displacement on the electrical outputs of the TENG unit and EMG unit are investigated systematically. The maximum output energy of TENG and maximum power of EMG can reach 21.7 mu J and 8.23 mu W respectively at fixed working frequency of 4.0 Hz and sliding displacement of 3.5 cm. In addition, those two basic units are assembled vertically into a sealed cylinder acrylic shell which is used to drive LEDs by harvesting the water wave energy. This work presents a novel and efficient approach toward large-scale blue energy harvesting from the ocean.