LEDs could offer portable sterilization
By Canadian Packaging staffDesign & Innovation Food Safety General Sustainability Bottling Coding & Labeling Deep UV LED Ohio State University water sterilization
New LEDs made from a light, flexible metal foil developed for portable drinking water purification.
Ohio State University scientists have created a flexible, lightweight LED (light-emitting diode) metal foil that can help sterilize medical equipment or purify drinking water.
The process uses deep UV high-energy light to kill bacteria.
Deep UV is already used by the military and humanitarian agencies to detect dangerous bacteria and even to cure plastic via deep-UV mercury lamps—but the problem is that they have always been too large and bulky for portable transport.
The other problem is that mercury is toxic
With the small LEDs, the same purification process is easy to transport, safe and inexpensive.
According to Ohio State associate professor of materials science and engineering Roberto Myers, the field of nanophotonics has always been limited commercially, because it couldn’t be made larger to use properly.
But, now, he says, they can make a sheet of them and consider using nanophotonics for large-scale manufacturing.
Here’s the science:
Using the previously established semiconductor growth system of molecular beam epitaxy, it uses vaporized elemental materials to settle on a surface to self-organize into layers known as nanostructures.
The Ohio State University scientists use this technique to grow a “carpet” of tightly-packed aluminum gallium nitride wires (nanowires)on pieces of metal foil made of titanium and/or tantalum.
These nanowires are a scant 20-50 nanometers wide and 200 nanometers high, which for reference sake is many thousand times thinner than a human hair.
These nanowires on the metal foil will light up brighter than more-expensively produced—and less flexible‚ single crystal silicon.
Could the Nanofoil LED eventually be used to increase food and beverage shelf-life? Canadian Packaging leaves that up to those who think big by thinking small.
Image above: by Brelon J. May, courtesy of Ohio State University.