Berkeley, CA - In a development that holds much promise for the future of solar cells made from nanocrystals, and the use of solar energy to produce clean and renewable liquid transportation fuels, researchers with the U.S. Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have reported a technique by which the electrical conductivity of nanorod crystals of the semiconductor cadmium-selenide was increased 100,000 times.
"The key to our success is the fabrication of gold electrical contacts on the ends of cadmium-selenide rods via direct solution phase-growth of the gold tips," says Paul Alivisatos, interim-Director of Berkeley Lab, who led this research. "Solution-grown contacts provide an intimate, abrupt nanocrystal-metal contact free of surfactant, which means that unlike previous techniques for adding metal contacts, ours preserves the intrinsic semiconductor character of the starting nanocrystal."
Alivisatos is a chemist who holds joint appointments with Berkeley Lab's Materials Sciences Division, and with the University of California-Berkeley where he is the Larry and Diane Bock professor of Nanotechnology. He is an internationally-recognized authority on nanocrystal growth and the corresponding author of a paper published in the on-line edition of Nano Letters entitled: "Enhanced Semiconductor Nanocrystal Conductance via Solution Grown Contacts."
Co-authoring the paper with Alivisatos were Matthew Sheldon and Paul-Emile Trudeau, members of Alivisatos' research group; Taleb Mokari, of Berkeley Lab's Molecular Foundry; and Lin-Wang Wang, in Berkeley Lab's Computational Research Division.
With the world demand for energy projected to more than double by 2050 and more than triple by the end of the 21st century, it is imperative that sustainable and carbon-neutral energy technologies be developed. The use of sunlight to generate electricity as well as to split water molecules for the pro
|Contact: Lynn Yarris|
DOE/Lawrence Berkeley National Laboratory