Nanogenerators to power iPods “within five years”

Scientists have shown off a nanogenerator that could soon power consumer electronics devices such as mobile phones and iPods.

The researchers at Georgia Tech’s School of Materials Science and Engineering have harvested mechanical energy – which could come from footsteps, a heartbeat or machine vibrations – to run nanogenerators that convert the energy into electricity.

“By simplifying our design, making it more robust and integrating the contributions from many more nanowires, we have successfully boosted the output of our nanogenerator enough to drive devices such as commercial liquid-crystal displays, light-emitting diodes and laser diodes,” said Zhong Lin Wang, lead professor on the project.

We are within the range of what’s needed and I believe we will be able to power small systems in the next five years

“If we can sustain this rate of improvement, we will reach some true applications in healthcare devices, personal electronics, or environmental monitoring.”

According to Wang, his nanogenerators rely on the piezoelectric effect seen in crystalline materials such as zinc oxide, which create an electric charge when flexed or compressed.

By capturing and combining the electrical output from millions of nanoscale zinc oxide wires, Wang claims his team can already produce as much as three volts – and up to 300 nanoamps.

The breakthrough involved developing a better way of manufacturing the nanowires into a multilayer composite, with polymer in between the zinc oxide veins. When flexed, these SIM-card sized nanowire sandwiches generated enough power to drive a commercial LCD purloined from a pocket calculator.

While current nanogenerator output remains below the level required for MP3 players or smartphones, Wang believes those levels will be reached soon.

“From when we got started in 2005 until today, we have dramatically improved the output of our nanogenerators,” Wang said, citing a 100-fold improvement in the last year alone.

“We are within the range of what’s needed and I believe we will be able to power small systems in the next five years.”