A handle coating with microbe-killing powers is activated by UV light whenever the door moves, two young researchers have shown.
Sum Ming Wong, 17, and Kin Pong Li, 18, of Hong Kong have developed a self-sanitising door handle powered by opening and closing the door. The movement creates power that triggers a germ-killing reaction, with around 99.8 per cent of microbes destroyed during lab tests.
It is hardly a secret that public areas often hold lots of bacteria and viruses, so after doing research, the two teenagers learned that a mineral called titanium dioxide is what will kill it. Wong and Li ground the mineral, already used in paints and sunscreens, into a very fine powder to make their coating, Science News for Students reports.
“Titanium dioxide kills bacteria best when lit by UV light,” said Wong. To allow that to happen, they built their door handle from a long cylinder of clear glass, with each end fitting into a bracket. Inside one of the brackets is a LED that flashes UV light from one end to the other, similar to the way in which light travels though a fibre-optic cable.
The power that makes the handle shine comes from the back-and-forth movement of the door, as a small gearbox attached to the door converts the motion into power. The power is then carried by wire to the light-emitting diode inside the handle.
The boys presented their research at the Intel International Science and Engineering Fair in the US, an annual competition sponsored by Intel which this year brought 1,702 finalists to Pittsburgh from more than 70 countries.