Electrical Energy from Stretching Yarn

by Emil Morhardt

Well, yarn, sort of. This yarn is made by twisting carbon nanotubes until they become so twisted that the coil up into a helical spring-like configuration. You can do the same thing with cotton yarn or string. When the South Korean researchers (Kim et al., 2017) put the coil into an electrolyte then stretched it what they got was electrical current. Not a lot, but these are small laboratory-scale experiments and what the researchers had in mind was generating small amounts of energy to power sensors, for example, sewn into a shirt or gloves that are stretched and released under normal activities, but that wouldn’t work very well if the subject had to be immersed in an electrolyte. Or would it? They tried immersing the device, which they call a twistron, into the Gyeonpo Sea off South Korea where the temperature was 13ºC (a chilly 55ºF) and the sodium chloride content was 0.31 M, a nice electrolyte solution. But instead of sewing the yarn into a diver’s wetsuit, they attached it between a floating balloon and a sinker on the seabed to see if they could harvest ocean wave energy. Yes! They got it to light up a green LED whenever a wave came by. Continue reading

South Korean Scientists Develop New, More Efficient Method of Producing Hydrogen

by Gage Taylor

Inspired by the way plants convert sunlight into energy, scientists at the Ulsan National Institute of Science and Technology in South Korea have developed a new type of photoelectrode that boosts the ability of solar water-splitting to produce hydrogen, an essential process in the development of hydrogen as a fuel source. The special photoelectrode is capable of absorbing a high percentage of visible light from the sun and then using it to split water molecules into hydrogen and oxygen. The multilayered photoelectrode has a two-dimensional hybrid metal-dielectric structure that consists of three layers: gold film, ultrathin TiO2 (titanium dioxide), and gold nanoparticles. According to the team’s study published last month in Nano Energy, this structure shows high light absorption, which in turn significantly enhances its photocatalytic applications. Continue reading