Today’s Solutions: December 18, 2025

Door handles tend to be home to alarmingly high levels of bacteria. That’s why a team of graduates from the University of Hong Kong have designed a door handle that uses light to constantly sterilize itself.

Comprised of a glass tube with aluminum caps at each end, the door handle is covered in a photocatalytic coating, made from a mineral called titanium dioxide, which is ground into a fine powder. This thin coating on the glass tube is able to decompose bacteria via a chemical reaction that is activated by UV light. In tests, the newly developed germ-killing design destroyed around 99.8 percent of microbes during lab tests.

To power the UV light, the handle doesn’t need batteries but rather converts kinetic energy from the frequent movement of the door opening and closing. Pretty neat.

The two designers were particularly driven by the SARS outbreak of 2003, which infected more than 8,000 people worldwide and caused more than 700 deaths, the majority of them in China and Hong Kong. The self-sanitizing door handle was one of the winning entries in the 2019 James Dyson Awards and is now under consideration in the final round of the competition.

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