Thermally induced hex-graphene transitions in 2D carbon crystals

Nanotechnology Reviews

卷:11

Xu Ke¹  Xu Yihua¹  Zhang Zhisen¹  Liu Yisi¹  Wu Jianyang¹  Lin Yanwen¹  Fu Ran¹  Chang Yuanhao²  Fu Yuequn² 

[1] Department of Physics, Research Institute for Biomimetics and Soft Matter, Jiujiang Research Institute and Fujian Provincial Key Laboratory for Soft Functional Materials Research, Xiamen University, Xiamen 361005, China;

[2] Department of Structural Engineering, NTNU Nanomechanical Lab, Norwegian University of Science and Technology (NTNU), Trondheim 7491, Norway;

关键词: 2d carbon crystals;    thermal properties;    structural transformations;    melting;    molecular dynamics;   

DOI  :  10.1515/ntrev-2022-0066

来源: DOAJ

【 摘 要 】

Resourceful beyond-graphene two-dimensional (2D) carbon crystals have been proposed/synthesized; however, the fundamental knowledge of their melting thermodynamics remains lacking. Here, the structural and thermodynamic properties of nine contemporary 2D carbon crystals upon heating are investigated using first-principle-based ReaxFF molecular dynamics simulations. Those 2D carbon crystals show distinct evolution of energetic and Lindemann index that distinguish their thermal stabilities. There are two or three critical temperatures at which structural transformation occurs for non-hexagon-contained 2D carbon allotropes. Analysis of polygons reveals that non-hexagon-contained 2D carbon crystals show thermally induced hex-graphene transitions via mechanisms such as bond rotations, dissociation, and reformation of bonds. The study provides new insights into the thermodynamics and pyrolysis chemistry of 2D carbon materials, as well as structural transitions, which is of great importance in the synthesis and application of 2D materials in high-temperature processing and environment.

【 授权许可】

Unknown