Searching for a power outlet may soon become a thing of the past.
Chinese and US researchers have developed a small metallic tab that when attached to the body, can generate electricity from bending a finger and other simple body movements.
Electronic devices will receive electricity from the tab – a triboelectric nanogenerator – China’s Xinhua news agency reported on Monday (Feb 12).
A study, published online recently in the journal Nano Energy, said the tab measures 1.5cm long and 1cm wide. It delivers a maximum voltage of 124 volts, a maximum current of 10 microamps and a maximum power density of 0.22 milliwatts per square centimetre.
While the power generated is not enough to quickly charge a smartphone, the device managed to light up 48 red LED lights simultaneously.
HOW IT WORKS
Most everyday static electricity is triboelectric, according to the collaborative research led by the University at Buffalo (UB) and the Institute of Semiconductors (IoP) at the Chinese Academy of Sciences (CAS).
“No one likes being tethered to a power outlet or lugging around a portable charger. The human body is an abundant source of energy. We thought: ‘Why not harness it to produce our own power?'” said lead author Qiaoqiang Gan and associate professor of electrical engineering in UB’s School of Engineering and Applied Sciences, as quoted in a news release.
The tab that the research team is developing addresses both concerns about the difficulty of manufacturing the device and its cost-effectiveness.
It consists of two thin layers of gold, with polydimethylsiloxane (PDMS), a silicon-based polymer used in contact lenses, silly putty and other products, sandwiched in between.
Key to the device is that one layer of the gold is stretched, causing it to crumple upon release and create what looks like a miniature mountain range. When that force is reapplied, for example from a finger bending, the motion leads to friction between the gold layers and PDMS.
“This causes electrons to flow back and forth between the gold layers. The more friction, the greater the amount of power is produced,” said another lead author, Yun Xu, a professor from the IoP at CAS.
The team also plans to use larger pieces of gold, which when stretched and folded together are expected to deliver even more electricity.
Next, researchers are working to develop a portable battery to store energy produced by the tab, according to the news release.
They envision the system serving as a power source for various wearable and self-powered electronic devices.