Remember the bizarre concept of turning plastic soda bottles into diamonds? Back in September 2022, we reported on a fascinating experiment in which German scientists used powerful lasers to transform ordinary bottle plastic into microscopic diamonds. Now the researchers have reached another milestone: for the first time, they have successfully captured the tiny diamonds intact, using a special gel.
Unfortunately, these aren't the kind of diamonds we will be setting into an engagement ring. Each one measures just three nanometers across — about three billionths of a meter — and contains roughly 3,000 carbon atoms. They're so small that even a trillion of them would barely make a visible impression. But what they lack in size, they make up for in scientific potential.
The original discovery was actually a byproduct of research into the interiors of icy giant planets, such as Neptune and Uranus. Scientists wanted to recreate the extraordinary conditions found deep inside these distant worlds, where temperatures reach several thousand degrees Celsius and pressure is millions of times greater than Earth's atmospheric pressure.
To do that, researchers at Germany's Helmholtz-Zentrum Dresden-Rossendorf and the University of Rostock fired high-powered laser pulses at an ultrathin film of polyethylene terephthalate, better known as PET — the everyday plastic used in water and soda bottles. The laser generated intense heat and shock waves, compressing the material so dramatically that its carbon atoms rearranged themselves into diamonds. The process also helps explain why scientists believe it literally rains diamonds inside Neptune and Uranus.
There was just one problem. The newly formed nanodiamonds were blasted out of the plastic at speeds exceeding 22,000 miles per hour. Trying to collect them was a little like attempting to catch a meteorite with a butterfly net. Until now, researchers could demonstrate that the diamonds formed, but couldn't recover them for closer examination.
The breakthrough came with a specially developed, water-soluble ionic gel. Acting as a soft cushion, the gel slowed the microscopic projectiles without destroying them. After extracting and purifying the particles, the team was finally able to examine individual nanodiamonds under an advanced electron microscope.
The results, recently published in the journal Diamond and Related Materials, could have implications far beyond planetary science. Nanodiamonds are exceptionally hard, stable and heat-resistant, making them useful in industrial grinding and polishing. Their potential future applications include highly sensitive quantum sensors, improved medical imaging and targeted drug delivery. They may also help speed up chemical reactions, including processes that use sunlight to break down carbon dioxide.
The researchers say the laser technique could eventually provide a cleaner, more controlled way to manufacture uniform, high-purity nanodiamonds than conventional methods. For now, they're working to increase production.
It's remarkable to think that yesterday's soda container could become tomorrow's high-tech diamond. That's quite a recycling story!
Credit: Conceptual image by The Jeweler Blog using aichatapp.ai.