Enhancement of the tubular liquid-solid triboelectric nanogenerator by coupling electrode pairs

Liquid-solid triboelectric nanogenerator has the advantages of little abrasion on the frictional interface and large frictional contact area, which is a promising way to harvest blue wave energy. To improve the output of liquid-solid triboelectric nanogenerator (LS-TENG), an original tube-based liquid-solid triboelectric nanogenerator with coupling electrode pairs (CEP-TENG) was proposed in this work. By adding internal electrodes, the friction contact area between deionized (DI) water and polytetrafluoroethylene (PTFE) is enlarged. It is demonstrated through experiments and simulations that the internal electrodes have little effect on the output of external electrode pair. CEP-TENG with a pair of internal electrodes in a length of 80 mm enhanced the short-circuit current and transfer charges from 0.11 μA, 34.78 nC to 0.21 μA, 57.34 nC, which were increased by 90.9 % and 64.86 % respectively. Moreover, the optimal volumetric output power was increased by 4.82 times. The output performances of CEP-TENG with different internal electrodes and volumetric fractions of water were all improved and widely adapt to diverse kinematic parameters. The results demonstrated that the original CEP-TENG is suitable for the efficient harvest of diverse water waves distributed in different sea areas.