Scientists at the University at Buffalo in the US, working alongside the Institute of Semiconductors at the Chinese Academy of Science, have developed a small metallic tab which, when attached to the human body, can generate electricity from small movements of the human body.

The tab - called a triboelectric nanogenerator - is 1.5cm long and 1cm wide, and can deliver a maximum of 124 volts, a current of 10 microamps and a power density of 0.22 millwatts per square centimetre.

The tab consists of two thin layers of gold, with polydimethylsiloxane (also called PDMS -- a silicon-based polymer used in contact lenses sandwiched in between.

When force is applied, for example, by bending a finger, the friction between the gold layers and PDMS, causes electrons to flow back and forth between the gold layers, generating tiny sparks of electricity.

Experiments found that by just the movement of a finger, the tab was able to power 48 LED lights.

Although the research is in its infancy, the researchers believe that the principal applications of the device could be charging a mobile phone or other small portable devices .

Speaking to the the Nano Energy journal, Professor Qiaoqiang Gan, from the University of Buffalo's School of Engineering and Applied Sciences, said, ‘The human body is an abundant source of energy. We thought: Why not harness it to produce our own power?’