A Kelp Inspired High-Power Density Triboelectric Nanogenerator with Stacking Structure for Multiple Directional Ocean Wave Energy Harvesting

Ocean wave energy is one of the most promising green energies in the wild. However, it is still challenging to effectively collect wave energy due to its randomness and irregularity. In this work, a kelp inspired high-power density triboelectric nanogenerator (K-TENG) is presented for harvesting wave energy with characteristics in multiple directions. The proposed K-TENG consists of a series of stacked leaf-like units. The influence of configuration parameters, including pellet diameters, pellet numbers, unit sizes, oscillation frequency, swing amplitude, and wave directions on output performances of leaf-like units, are extensively investigated. Experimental data indicates that a single leaf-like unit can achieve a maximum output voltage of 623.14 V as well as a maximum current of 1.48 µA and realize energy harvesting from different wave directions. A K-TENG composed of 15 leaf-like units demonstrates a high-power density of 18.77 W m⁻³ at a wave frequency of 2.5 Hz, which successfully powers a digital watch and 414 light-emitting diodes (LEDs). This work is hoped to provide a simple and reliable route to effectively harvest ocean wave energy.