U.S. Department of Energy

    Carbon Nanotubes Show Promise for Solar Cells, Other Devices

    August 24, 2005

    GE Global Research announced a breakthrough on August 18th that could lead to a new generation of solar cells, as well as a wide variety of electronic devices. The organization, which is the central research arm of General Electric Company, has developed a diode from carbon nanotubes—tubes of carbon on the scale of about a billionth of a meter—that operates at the best possible performance for diodes, the theoretical limit. The diode is also able to convert sunlight into electricity, which means it could be used to build a solar cell. Diodes are the fundamental building block for many electronic devices, including solar cells, transistors, computer chips, sensors, and light-emitting diodes (LEDs), so an ideal diode could result in a wide variety of more efficient devices. GE published the research in the August 15th issue of Applied Physical Letters. See the GE press release.

    One problem with nanotubes is the difficulty of assembling these sub-microscopic materials into a usable product, a barrier that researchers at the University of Texas at Dallas (UTD) claim to have overcome. In research published in the August 19th issue of Science, the UTD researchers claim to be able to fabricate sheets of nanotubes at a rate of seven meters per minute. The resulting sheets have a number of amazing properties: they are transparent, extremely lightweight, highly conductive, and stronger than steel. The research team believes the sheets could have applications in either LEDs or solar cells, as well a wide variety of other applications. The UTD research was performed in collaboration with an Australian national laboratory, the Commonwealth Scientific and Industrial Research Organization (CSIRO). See the UTD press release.