From the ACS Press Room
Plugging into Ocean Waves with a Flexible, Seaweed-like Generator (video) “Flexible Seaweed-Like Triboelectric Nanogenerator as a Wave Energy Harvester Powering Marine Internet of Things”
tinuous movement as a renewable energy source, researchers initially developed floating devices that converted wave energy into electricity using rotating magnets. But these ACS Nano devices were inefficient with less frequent Ocean waves can be powerful, containing waves, such as those found underwater. Trienough energy to push around sand, pebbles boelectric nanogenerators (TENGs), which and even boulders during storms. These rely on surfaces coming in contact to produce waves, as well as smaller, more gentle ones, static electricity, could be a way to address could be tapped as a source of renewable en- this challenge because of their effectiveness ergy. Now, researchers reporting in ACS for harvesting low-frequency, low-amplitude Nano have developed flexible power genera- wave energy. So, Minyi Xu, Zhong Lin Wang tors that mimic the way seaweed sways to and colleagues were inspired by plants living efficiently convert surface and underwater on the seafloor to create flexible TENGs. The waves into electricity to power marine-based researchers wanted to copy the way strands devices. Watch a video of the seaweed-like of seaweed vibrate to charge bendable triboepower generators. lectric surfaces, harvesting the movement of waves into electricity to power floating and submerged marine sensors. To make the triboelectric surfaces, the reYoutube ID: XuVKRhRMogY searchers coated 1.5-inch by 3-inch strips of two different polymers in a conductive ink. Then a small sponge was wedged between the strips, creating a thin air gap, and the Across many coastal zones, networks of sen- whole unit was sealed, creating a TENG. In sors collect information on the water’s cur- tests, as the TENGs were moved up and rents, tides and clarity to help ships navigate down in water, they bent back and forth, genand to monitor water quality. This “marine erating electricity. When the researchers put internet of things” is powered mostly by bat- the TENGs in water pressures similar to teries that have to be replaced from time to those found underwater in coastal zones, they time, which is time-consuming and expen- found that the air gap between the two consive. Wind and solar power could be used, ductive materials decreased. However, the but they aren’t suitable for underwater appli- devices still generated a current at 100 kPa of cations. Looking to harness the ocean’s con- pressure — the same pressure that typically exists at a 30-foot water depth where there is November 2021
The Southwest RETORT
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