Material Harder Than Diamond.
Researchers from Troitsk have developed a new method for the synthesis of an ultra-hard material from spherical molecules made of carbon atoms that exceeds diamond in hardness.
In their work, the scientists note that diamond hasn't been the hardest material for some time now. Ultrahard fullerite has surpassed diamond to become first on the list of hardest materials.
This is a carbon molecule in the form of spheres consisting of 60 atoms. The carbon spheres can be arranged in different ways, and the material's hardness largely depends on just how interconnected they are. In the ultrahard fullerite discovered by the workers C 60 molecules are interconnected by covalent bonds in all directions.
What makes synthesizing fullerite in large quantities so difficult is the high pressure required for the reaction to begin. Formation of the three-dimensional polymer begins at a pressure of 13 GPa, or 130,000 atm. But modern equipment cannot provide such pressure on a large scale.
The scientists in the current study have shown that adding carbon disulfide (CS2) to the initial mixture of reagents can accelerate fullerite synthesis. In addition, while previous efforts to synthesize fullerite at a pressure of 13 GPa required heating up to 1100K (more than 820 degrees Celsius), in the present case it occurs at room temperature.
Source: science daily
17-09-2014 12:56 PM