541 / 2019-03-20 11:00:28

Superhard Semiconducting Amorphous Carbon

Amorphous carbon; Fullerene; High pressure; Superhard

全体主题 > High Pressure Physics and Materials Science

Element carbon can exit in diverse polymorphs with fascinating physical and chemical properties because of its variable sp, sp2 and sp3 bonding. Considerable efforts have been made to explore new carbon member for more captivating results in scientific research. Here, we reported a class of novel sp2-sp3 amorphous carbons with highly sp3 bonding, exhibiting extremely high density and hardness. A previously unattainable pressure and temperature conditions have been adopt in our experiments to recover the targets from compressing C60 fullerene. Various hardness measurements demonstrate that the amorphous carbons are the hardest amorphous materials ever made, and can scratch diamond. This class of amorphous carbons also show excellent electrical properties that are semiconducting with tunable bandgaps of 1.5-2.2 eV comparable to that of amorphous silicon. The uniqueness of this type of carbons is that they are the densest, hardest amorphous carbons, and have the potential to be the optimal semiconductors for photoelectric applications.