Dr. Zhong Lin Wang, in conjunction with his School of Materials Science and Engineering colleagues at the Georgia Institute of Technology, has developed improved nanotechnology power generators that take mechanical energy from the body’s muscular motion and converts it into electrical power. The nanogenerator was unveiled at the 241st National Meeting & Exposition of the American Chemical Society.
The power is sufficient to drive LCD displays or send a radio signal, with the objective of eventually powering electronic devices such as iPods, cell phones and internal medical devices. Embedded insulin pumps could be powered by heartbeats, and other medical sensors could be powered by these nanogenerators, using radio waves to send monitoring information from inside the body without using a battery or electrical connections.
“Our bodies are good at converting chemical energy from glucose into the mechanical energy of our muscles ... These nanogenerators can take that mechanical energy and convert it to electrical energy for powering devices inside the body. This could open up tremendous possibilities," explained Wang.
Nanogenerators use zinc oxide nanowires that produce electricity when mechanically stretched. The generated power can be stored in a capacitor, negating the need for a battery. This nanotech generator’s power output has been improved by 1000 fold, and the voltage output has also been increased 150 times compared to previous versions.
Body movement like walking, a heartbeat or even blood flow, can provide mechanical power input to the nanogenerator. The nanowires, 500 of which fit inside the diameter of a human hair, can also generate electrical output from vibrating in the wind or from rolling car tires.
Millions of nanoscale zinc oxide wires are placed on a polymer chip to make a nanogenerator, and five nanogenerators are connected together to produce around 1mA at 3V (0.003W), so many more nanogenerators would need to be strung together to power a cell phone or iPod.