Hu, Meng; Zhang, Shuangshuang; Liu, Bing; Wu, Yingju; Luo, Kun; Li, Zihe; Ma, Mengdong; Yu, Dongli; Liu, Lingyu; Gao, Yufei; Zhao, Zhisheng; Kono, Yoshio; Bai, Ligang; Shen, Guoyin; Hu, Wentao; Zhang, Yang; Riedel, Ralf; Xu, Bo; He, Julong; Tian, Yongjun
Glassy carbon (GC) is a type of non-graphitizing disordered carbon material at ambientpressure and high temperatures, which has been widely used due to its excellent mechanicalproperties. Here we report the changes in the microstructure and mechanical properties of GCtreated at high pressures (up to 5 GPa) and high temperatures. The formation of intermediatesp2sp3 phases is identified at moderate treatment temperatures before the completegraphitization of GC, by analyzing synchrotron X-ray diffraction, Raman spectra, andtransmission electron microscopy images. The intermediate metastable carbon materials exhibit superior mechanical properties with hardness reaching up to 10 GPa and compressive strength reaching as high as 2.5 GPa, nearly doubling those of raw GC, and improving elasticity and thermal stability. The synthesis pressure used in this study can be achieved in the industry on a commercial scale, enabling the scalable synthesis of this type of strong, hard, and elastic carbon materials.