Experimental study of high performance mercury-based triboelectric nanogenerator for low-frequency wave energy harvesting

Abstract

Wave energy is acknowledged as one of the most promising renewable energy sources, effectively developing wave energy conversion technologies might contribute to solving the power shortage dilemma. However, the optimum performance frequency range of current wave energy capture devices does not match the low-frequency ocean kinetic energy. Here, a triboelectric nanogenerator based on liquid mercury (M-TENG) is presented for low-cost and high-power harvesting. The start-up performance of the M-TENG unit is analyzed at low operating frequencies, and discuss the effect of kinematic inputs, structural parameters and materials aspects on output performance. Meanwhile, the sloshing characteristics of mercury in a rectangular unit were calculated by the SST k-ω model, deriving the matching law between mercury volume and electrical output. Furthermore, 18-unit integrated M-TENG produce a peak power output of 4.57 mW, the mercury with its unique physical properties generates higher transferred charge density up to 35.84 mC/m3, sufficient to light 270 commercial LEDs at 1.00 Hz. The relatively high volumetric power density provides a realistic self-supply technological solution for renewable energy harvesting and guarantees the widespread use of milliwatt power equipment in the marine industry.