Follow EB-5 Immigration and stay updated on U.S. scientific achievements: As renewable energy sources, solar and wind power have the major drawback of intermittency—sunny and windy days are not always guaranteed. In this regard, ocean waves offer an unparalleled advantage. Scientists at the U.S. Georgia Institute of Technology have developed a nanotriboelectric generator that uses ocean waves to generate electricity. Researchers state that this generator is simple in structure, inexpensive, easy to use, and capable of operating continuously day and night. The relevant paper has been published in the journal Angewandte Chemie.
The triboelectric effect is a phenomenon where electric charges are generated through the contact and separation of two materials. The team led by Zhong Lin Wang at the Georgia Institute of Technology, who is responsible for this research, previously developed a solid-state triboelectric generator capable of charging mobile phone batteries. The challenge for this new research was how to enable triboelectric power generation in a wet environment like seawater.
Researchers discovered that the triboelectric phenomenon is not limited to solids; it also exists in liquid environments. The only requirement is that the specific electron energy levels of the two substances are sufficiently close. For water, all it needs is a suitable "partner." Through experiments, they found that a special type of plastic could fulfill this role.
As a prototype, the researchers created an insulated plastic container. The container has a lid and a base, with electrodes made of copper foil installed on it. Their system succeeds because the interior of the lid is coated with a layer of nano-scale, micro-pyramid-shaped polydimethylsiloxane (PDMS), while the container is filled with deionized water. When the lid descends, these micro-pyramids come into contact with the water, causing a batch of PDMS atoms to ionize, thereby generating a negative charge; simultaneously, a corresponding positive charge is generated on the water surface. When the PDMS layer leaves the water and transfers the charge, a complete triboelectric generation process is finished.
The principle utilizes the potential difference between PDMS and water. PDMS was chosen for its excellent hydrophobicity, which reduces water adhesion, and its unique pyramid shape, which makes it easier for water to shed.
When placed in seawater, the device rises and falls periodically with the waves. The electrodes within are connected to a rectifier and a capacitor, and the generated direct current is capable of lighting up 60 LED bulbs. Researchers state that the device has broad application value. Because it is sensitive to temperature, it can be used as a temperature sensor; if other sensors are attached to it, it can also provide more imaginative possibilities for the design of biomolecular and chemical sensors.