BBC interviews Graduate Student Researcher, Chris Zollner

The little lights now packing a deadly punch

  • 29 May 2020

"The tech we are working on could transform water sanitisation techniques and offer access to clean drinking water to even remote developing regions via portable systems," says Christian Zollner from the University of California in Santa Barbara.

Mr Zollner has been working on light emitting diodes (LEDs), the long-lasting technology in modern lightbulbs. They are probably in the lightbulbs in your house, or the headlamps of your car.

Because they are tough and energy efficient, researchers are always trying to find new ways of using them.

Mr Zollner and his team have been working on LEDs that emit ultraviolet light, in particular UV-C light, which is deadly to bacteria and viruses, including the coronavirus.

His goal is to make those LEDs more powerful, robust and cheaper.

"Right now, UV LEDs are capable of a few milliwatts of power. Our aim is to make them 10 to 20 times more powerful.

"Our focus previously was mainly on using them for water sterilisation, but the Covid-19 pandemic has made us realise there is also a big market for sanitising surfaces and equipment. If there is another virus situation in say five or 10 years, this technology could be very useful."

At the moment his lights are powerful enough to cleanse a closed cabinet, but need to be 20 times more powerful to zap a whole room.

The light can also damage human skin and eyes, so the commercial applications are limited.

But one firm has found a use. Californian firm LARQ makes what it says is the world's first self-cleaning water bottle.

Its solution to prevent exposure to UV-C light is to ensure the tiny UV LEDs in the lids of its bottles only come on when the bottles are screwed shut.

Users must then push down on the lid to activate the technology, which the company claims eradicates more or less all bacteria and viruses in 60 seconds.

To support UVC-LED research at UCSB, click: