(May 8, 2012) With the age of the incandescent light bulb fading rapidly, the holy grail of the lighting industry is to develop a highly efficient form of solid-state lighting that produces high quality white light.
One of the
few alternative technologies that produce pure white light is white-light
quantum dots. These are ultra-small fluorescent beads of cadmium selenide that
can convert the blue light produced by an LED into a warm white light with a
spectrum similar to that of incandescent light. (By contrast, compact
fluorescent tubes and most white-light LEDs emit a combination of monochromatic
colors that simulate white light).
Seven years
ago, when white-light quantum dots were discovered accidentally in a Vanderbilt
chemistry lab, their efficiency was too low for commercial applications and
several experts predicted that it would be impossible to raise it to practical
levels. Today, however, Vanderbilt researchers have proven those predictions
wrong by reporting that they have successfully boosted the fluorescent
efficiency of these nanocrystals from an original level of three percent to as
high as 45 percent.