Phys.org November 24, 2021
An international team of researchers (China, USA – Carnegie Institution for Science, Germany, Sweden) has synthesized millimetre-sized samples of transparent, nearly pure sp3 amorphous carbon by heating fullerenes at pressures close to the cage collapse boundary. The material synthesized consists of many randomly oriented clusters with diamond-like short-/medium-range order and possesses the highest hardness, elastic modulus and thermal conductivity observed in any known amorphous material. It also exhibits optical bandgaps tunable from 1.85 eV to 2.79 eV. The ultrahard form of carbon glass with a wealth of potential practical applications for devices and electronics. The use of new glass materials hinges on making large pieces, which has posed a challenge in the past. The comparatively lower temperature at which they were able to synthesize this new ultrahard diamond glass makes mass production more practical…read more. TECHNICAL ARTICLEÂ
Optical photographs of the recovered samples from different HPHT conditions. Credit: Nature volume 599, pages599–604 (2021)