Two novel superhard carbon allotropes with honeycomb structures
At a Glance
Section titled āAt a Glanceā| Metadata | Details |
|---|---|
| Publication Date | 2019-10-14 |
| Journal | Journal of Applied Physics |
| Authors | Wei Zhang, Changchun Chai, Qingyang Fan, Yanxing Song, Yintang Yang |
| Institutions | Xiāan University of Architecture and Technology, Xidian University |
| Citations | 47 |
Abstract
Section titled āAbstractāTwo novel superhard 3D sp3 hybridized carbon allotropes (Cmmm-C32 and P6/mmm-C54) are proposed in this work through first-principles calculations. Both Cmmm-C32 and P6/mmm-C54 have a honeycomb structure. P6/mmm-C54 shows a wide direct bandgap (3.564 eV), while Cmmm-C32 shows an ultrawide indirect bandgap (5.051 eV), as determined using the HSE06 hybrid functional. The hardnesses of Cmmm-C32 and P6/mmm-C54 are 83.72 and 54.01 GPa, respectively, and their calculated ideal strengths further confirm their superhardness characteristics. P6/mmm-C54 is isotropic in the (001) plane. The minimum thermal conductivities of Cmmm-C32 and P6/mmm-C54 are larger than those of diamond-C, illustrating that Cmmm-C32 and P6/mmm-C54 are potential semiconductor device materials.