You can stop puzzling over what to do with those unwanted recordable CDs.
Researchers at the University of São Paulo in Brazil have developed a way
to make electrodes out of the pre-polished gold that lines them. Using nitric
acid, they removed the CD’s plastic layers to reveal the gold layer, which is
about 50 to 100 nanometres thick. The gold is the perfect thickness for use in
many types of electrolytic cells—particularly those used to measure levels
of mercury and copper in drinking water.
To continue reading, today with our introductory offers
Advertisement
More from New Scientist
Explore the latest news, articles and features
Popular articles
Trending New Scientist articles
1
The world's fastest spider tops 3.5 metres per second
2
Babies are born with the neural foundations for maths
3
Where, when and how to watch the 2026 solar eclipse
4
A type of fibre that stimulates GLP-1 release approved for use in food
5
The best new science-fiction novels published in July 2026
6
The weirdness of neutrinos could completely rewrite particle physics
7
Slowdown of AMOC ocean current may be gradual and reversible
8
US government wants to have a useful quantum computer by 2028
9
We’re not the most successful human species
10
I’m the first person whose life was saved by CRISPR base editing
