The next not-so-big thing: nanogenerators

Just as a machine won’t run without a source of power, a device built at the nano-scale is of little use if it doesn’t have the energy to work as a sensor or drug delivery particle. Since there isn’t a battery in existence yet that’s small enough to couple with a nanodevice, researchers have sought to power their microscopic creations with energy drawn from their surroundings. This energy so far has come primarily from chemical reactions (such as the oxidation of hydrogen peroxide), but that may change. A new study published today in Science describes the creation of a nanogenerator that transforms kinetic energy into a continuous flow of direct-current (DC) electrical energy.
Zhong Lin Wang, director of the Center for Nanostructure Characterization at the Georgia Institute of Technology, says the kinetic energy can come from a variety of sources, including ultrasonic waves, mechanical vibration or blood flowing through the body.

Such generators could be used to power sensors for detecting cancer or measuring blood sugar level for diabetics, Wang says. He adds that within five to 10 years, the technology will mature to the point that these generators could be placed in the soles of shoes or the fabric of clothes so that people will be able to power their iPods and cell phones using the mechanical energy created by the rustling of their clothes or compression of their shoe insoles as they walk.

Scientifc American