In its natural existence, oceans cover nearly 70% of the surface of the Earth and is the largest source of energy. Meanwhile, to tap the abundance of oceanic energy is the quest of researchers in a bid to solve the energy crisis and greenhouse gas emissions by thermal power generation. In fact, the nanogenerator, which includes piezoelectric, triboelectric, and pyroelectric nanogenerators is one of the key techniques for mechanical energy conversion. In terms of function, the triboelectric nanogenerator uses triboelectric effect and electrostatic induction to produce mechanical energy based on sliding or contact electrification.
However, mostly, conventional triboelectric nanogenerators are based on solid contact, and to ensure the contact intimacy of two tribo materials is hard. In fact, the material surfaces wear or get damaged after long-term friction. Moreover, the solid triboelectric nanogenerators need shell mechanical components such as holders, springs, and rotors to generate random vibration energy. The complex structure of triboelectric nanogenerators reduces the efficiency of energy generation.
Following a recent research initiative, the technical limitations of conventional triboelectric nanogenerators and developed a water-tube-based version for irregular and low-frequency environmental harvesting of energy such as water waves. To do this, the researchers encapsulated water in a tube of the size of a finger. In such a structure, with the flow of water in the tube between areas of the two electrodes, this results in triboelectrification and generation of electric current.
In fact, with the flexibility of water, the water-tube-built triboelectric nanogenerator can be operated in a number of modes. This includes swing, rotation, seesaw, and horizontal linear modes to generate energy from varied mechanical movements in the environment.