Sharon Weiss, an associate professor of electrical engineering at Vanderbilt University, and her colleagues developed a simple technique for stamping patterns invisible to the human eye onto a special class of nanomaterials, providing a new, cost-effective way to produce novel devices in areas ranging from drug delivery to solar cells.
For a number of years, scientists have been intrigued by a special class of materials, called porous nanomaterials, because they have unique optical, electrical and mechanical properties. Imagine stiff, sponge-like materials filled with holes that are too small to see without a special microscope. One of the major obstacles to using these materials--there are nanoporous forms of gold, silicon, alumina and titanium oxide, among others--has been the cost and complexity of the processes that have been used to transform them into devices for use in drug delivery, chemical and biological sensors, solar cells and battery electrodes.
Several years ago, Weiss got the idea of using the complex ultraviolet and electron beam lithography processes that have been used to make devices out of porous nanomaterials to produce stamps instead, making devices by direct imprinting. This low-cost process has proven that it can accurately imprint these special materials with the intricate patterns required. [The technique was described in the cover article of the May 2011 issue of the journal Nano Letters. ] Vanderbilt has applied for a patent on the new technique, called Direct Imprinting of Porous Suibstrates.
This research was supported in part by a Graduate Research Fellowship from the National Science Foundation. To learn more, see the Vanderbilt news story Stamping out low cost nanodevices. (Date of Image: 2006)