A simple technique for stamping patterns invisible to the human eye onto a special class of nanomaterials provides a new, cost-effective way to produce novel devices in areas ranging from drug delivery to solar cells. The technique was developed by Vanderbilt University engineers and described in the cover article of the May issue of the journal Nano Letters.
The new method works with materials that are riddled with tiny voids that give them unique optical, electrical, chemical and mechanical properties. Imagine a stiff, sponge-like material filled with holes that are too small to see without a special microscope. For a number of years, scientists have been investigating the use of these materials — called porous nanomaterials — for a wide range of applications including drug delivery, chemical and biological sensors, solar cells and battery electrodes. There are nanoporous forms of gold, silicon, alumina, and titanium oxide, among others.
A major obstacle to using the materials has been the complexity and expense of the processing required to make them into devices.
Now, Associate Professor of Electrical Engineering Sharon M. Weiss and her colleagues have developed a rapid, low-cost imprinting process that can stamp out a variety of nanodevices from these intriguing materials.
“It’s amazing how easy it is. We made our first imprint using a regular tabletop vise,” Weiss said. “And the resolution is