A high-output performance disc-shaped liquid-solid triboelectric nanogenerator for harvesting omnidirectional ultra-low-frequency natural vibration energy

Low-frequency vibrations, such as ocean waves, are widely distributed in nature and serve as a promising renewable energy source. Triboelectric nanogenerators (TENGs) have been shown to be an effective method for harvesting low-frequency vibration energy. However, most TENGs can only effectively harvest vibration energy in a single direction and a specific vibration mode. To solve the problem, we developed a disc-shaped liquid-solid triboelectric nano-generator (DLS-TENG) that can harvest vibration energy omnidirectionally. Benefiting from the high flexibility of the fluid and the ultra-high surface utilization of the disc structure, the DLS-TENG has the highest volumetric charge density and load driving capability in harvesting omnidirectional vibrational energy. Driven by seesaw vibrations with a frequency of 0.5 Hz and an amplitude of 30°, one DLS-TENG successfully lit up 544 LEDs simultaneously, with a transferred charge of 1263 nC. Considering the random, irregular, and variable characteristics of most ambient vibrations, our omnidirectional TENG is more practical. The proposed DLS-TENG can achieve long-term and efficient natural vibration energy harvesting to power an increasing number of microsensors widely distributed in the field.