Posted: May 14th, 2012 Research opens doors to UV disinfection using LED technology ( Nanowerk News ) Research from North Carolina State University will allow thedevelopment of energy-efficient LED devices that use ultraviolet(UV) light to kill pathogens such as bacteria and viruses. Thetechnology has a wide array of applications ranging fromdrinking-water treatment to sterilizing surgical tools. “UV treatment utilizing LEDs would be more cost-effective, energyefficient and longer lasting,” says Dr. Ram Collazo, an assistantprofessor of materials science and engineering at NC State and leadauthor of a paper describing the research. Clean Room Sticky Mat
“Our work would alsoallow for the development of robust and portable water-treatmenttechnologies for use in developing countries.” LEDs utilize aluminum nitride (AlN) as a semiconductor, because thematerial can handle a lot of power and create light in a widespectrum of colors, particularly in the UV range. However,technologies that use AlN LEDs to create UV light have beenseverely limited because the substrates that served as thefoundation for these semiconductors absorbed wavelengths of UVlight that are crucial to applications in sterilization and watertreatment technologies. A team of researchers from North Carolina and Japan has developed asolution to the problem. Using computer simulation, they determinedthat trace carbon atoms in the crystalline structure of the AlNsubstrate were responsible for absorbing most of the relevant UVlight. By eliminating the carbon in the substrate, the team wasable to significantly improve the amount of UV light that can passthrough the substrate at the desired wavelengths. China ESD Wrist Strap
“Once we identified the problem, it was relatively easy andinexpensive to address,” says Dr. Zlatko Sitar, Kobe SteelDistinguished Professor of Materials Science and Engineering at NCState and co-author of the paper. Commercial technologies incorporating this research are currentlybeing developed by HexaTech Inc., a spin-off company from NC State. “This is a problem that’s been around for more than 30 years, andwe were able to solve it by integrating advanced computation,materials synthesis and characterization,” says Dr. Rubber ESD Mat
Doug Irving,assistant professor of materials science and engineering at NCState and co-author of the paper. “I think we’ll see more work inthis vein as the Materials Genome Initiative moves forward, and that this approach will accelerate thedevelopment of new materials and related technologies.” The paper, “On the origin of the 265 nm absorption band in AlN bulk crystals” , is published online in Applied Physics Letters. Co-authorsinclude Benjamin Gaddy, Zachary Bryan, Ronny Kirste and MarcHoffman from NC State, as well as researchers from HexaTech Inc.,Tokyo University of Agriculture and Technology, and the TokuyamaCorporation. The research was supported with funding from the U.S.Department of Defense.