Scientists unveil hardest synthetic diamond ever made

Scientists unveil hardest synthetic diamond ever made

The resulting diamond is stable at temperatures up to nearly 1000°C – 200°C higher than natural gems.

Chinese researchers from Yanshan University have created a synthetic diamond harder than its natural counterpart and able to withstand even hotter temperatures.

The team, led by Yongjun Tian, say the new form of diamond could be used to make superior cutting or crushing tools, capable of operate under very extreme conditions.

The group made the diamond by heating carbon onions —concentric fullerene spheres nested within one another— at 2000°C and 25GPa, hundreds of thousands of times the pressure of Earth’s atmosphere. The resulting diamond has an extremely high hardness of around 200GPa and is stable at temperatures up to nearly 1000°C – 200°C higher than natural diamond.

“The scientific community has dreamt of synthesising novel materials harder than natural diamond for decades,” says Tian in an article published this week in the journal Nature.

The usual approach, he adds, is to try and create smaller and smaller grains within the material’s microstructure.

Because of its superior features, the synthetic diamond diamond can be use to manufacture industrial tools or scientific instruments —such as diamond anvil cells— that work at high temperatures.

The team is currently working on reducing the pressure needed to make each diamond by using finer carbon onions, so that they can be more easily manufactured.

Image by Ken Tannenbaum