Friday, October 23, 2009

This week in nanotechnology October 16-23, 2009

To boldly go where no one has gone before: A University of Michigan professor is developing an electric rocket thruster, NanoFET, that uses nanoparticle electric propulsion and enables spacecraft to travel faster and with less propellant than previous technology allowed.

Chemists at Idaho National Laboratory and Idaho State University have invented a way to manufacture highly precise, uniform nanoparticles to order. The technology, Precision Nanoparticles, has the potential to vastly improve the solar cell and further spur the growing nanotechnology revolution.

More than 120 years after the discovery of the electromagnetic character of radio waves by Heinrich Hertz, wireless data transmission dominates information technology. Higher and higher radio frequencies are applied to transmit more data within shorter periods of time. Some years ago, scientists found that light waves might also be used for radio transmission. So far, however, manufacture of the small antennas has required an enormous expenditure. KIT scientists have now succeeded for the first time in specifically and reproducibly manufacturing smallest optical nanoantennas from gold.

Taking nanomaterials to a new level of structural complexity, scientists have determined how to introduce kinks into arrow-straight nanowires, transforming them into zigzagging two- and three-dimensional structures with correspondingly advanced functions.

Scanning electron microscope of nanowires ready for device assembly using optical tweezers


This is a false-color scanning electron microscope image of the zigzag nanowires in which the straight sections are separated by triangular joints and specific device functions are precisely localized at the kinked junctions in the nanowires. (Image: Bozhi Tian, Lieber Group, Harvard University)


In another advance in nanofabrication technology, researchers with the Berkeley Lab have found a simple and yet powerfully robust way to induce nanoparticles to assemble themselves into complex arrays. By adding specific types of small molecules to mixtures of nanoparticles and polymers, the researchers are able to direct the self-assembly of the nanoparticles into arrays of one, two and even three dimensions with no chemical modification of either the nanoparticles or the block copolymers. In addition, the application of external stimuli, such as light and/or heat, can be used to further direct the assemblies of nanoparticles for even finer and more complex structural details.

Since all good things come in threes, in a third nanomanufacturing advance reported this week, scientists at Caltech have uncovered the physical mechanism by which arrays of nanoscale pillars can be grown on polymer films with very high precision, in potentially limitless patterns. This nanofluidic process could someday replace conventional lithographic patterning techniques now used to build three-dimensional nano- and microscale structures for use in optical, photonic, and biofluidic devices.

And finally, for those of you who are interested in finding out more about successful founding and financing of nanotechnology start-ups, Nanowerk and Nanostart have developed a new mini-series "Funding for nanotechnology companies".