Dielectric-Metal Triboelectric Nanogenerators for Ocean Wave Impact Self-Powered Applications

This paper describes the effect of oscillatory frequencies caused by ocean wave impact on the output performance of dielectric-metal contact separation mode triboelectric nanogenerators (DMCS-TENG). The triboelectric effect is generated as a result of regular, non-uniform contact between a dielectric layer which gains electrons (negative triboelectric material) and a conductive layer that loses electrons (positive triboelectric material). Impact testing was used to characterize arc-shaped dielectric-metal single electrode triboelectric nanogenerators (DMSE-TENG) with different triboelectric material combinations based on their output power generation, using a 40-mm ball bearing to apply a 12-N force impulse. It was found that the best dielectric-conductor combination for the DMCS-TENG performance was polyimide and PDMS in contact with the conductor layers of aluminum and silver conductive cloth tape. Therefore, in the range of operation from 30 to 300 Hz with an amplitude acceleration of 319.62 to 559.29 mm/
$\text{s}^{{2}}$
, the maximum generated output power, power density, and total energy conversion efficiency of the device, made with polyimide and honeycomb patterned aluminum foil, can reach up to
$778.43~\mu \text{W}$
,
$12.16~\mu \text{W}$
/cm
$^{{2}}$
, and 15.85 % respectively, for a load resistance of 10
$\text{M}\Omega $
. The output power performance of the DMCS-TENG shows an enhancement by a factor of 2.3 with a honeycomb-patterned aluminum foil, by increasing the surface charge density between the layers in contact, relative to flat aluminum foil. Additionally, through the integration of the energy harvester prototype into a water wave generator tank, an output power density of 169.218 mW/
$\text{m}^{{2}}$
was reached, where it is expected to generate output power energy around 3.05 W, over an area of 18
$\text{m}^{{2}}$
with wave sizes among 0.3 to 4 m. This paper demonstrates that the device can function as an energy harvesting mechanism for ocean wave sensing applications that require self-powering.