Carbon nanotubes with a lit fuel coating generate an electrical current, the result of a fast-moving combustion wave (thermal wave) traveling along the length of the carbon nanotube that drags electrons along, MIT scientists have discovered.

The system puts out about 100 times greater energy in proportion to its weight than a lithium-ion battery. In theory, says Michael Strano, MIT’s Charles and Hilda Roddey Associate Professor of Chemical Engineering, such devices could maintain their power indefinitely until used, unlike batteries, whose charges leak away gradually as they sit unused. And the nanowires could be made in large arrays to supply significant amounts of power for larger devices.

He suggests that one possible application would be in enabling new kinds of ultra-small electronic devices — for example, devices the size of  grains of rice, perhaps with sensors or treatment devices that could be injected into the body. Or it could lead to “environmental sensors that could be scattered like dust in the air.”

By using different kinds of reactive materials for the coating, the wave front could oscillate, thus producing an alternating current, the basis for radio waves such as cell phone transmissions.

More info: MIT news