Abstract Diamondene can be formed by compressing two or more layers of graphene. As a sp2/sp3 orbital hybridized two-dimensional material, its physical properties are different from either graphene or diamond. This new material is ultrahard on a SiC substrate. Here, we focus on the thermal stability and the basic mechanical properties of diamondene without passivation. We used molecular dynamics calculations to show that diamondene has isotropic thermal expansion at temperature below 280 K. At room temperature, it is unstable. When stretched along the armchair direction, diamondene has a maximum elastic strain that is higher than 0.17. It then experiences further plastic deformation before collapse. However, when stretched along the zigzag direction, the maximum elastic strain is higher than 0.3, e.g., 0.318 at 250 K. The ribbon collapses soon after the strain exceeds the critical value. Hence, diamondene has an elastic-brittle property along the zigzag direction. This excellent elasticity is significant for applications of diamondene in a flexible device.

中文翻译：

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金刚石烯在有限温度下的热性能和拉伸性能：分子动力学研究

摘要 金刚石烯可以通过压缩两层或多层石墨烯而形成。作为 sp2/sp3 轨道杂化二维材料，其物理性质不同于石墨烯或金刚石。这种新材料在 SiC 衬底上具有超硬性能。在这里，我们关注未经钝化的金刚石的热稳定性和基本机械性能。我们使用分子动力学计算表明，金刚石烯在低于 280 K 的温度下具有各向同性的热膨胀。在室温下，它是不稳定的。当沿扶手椅方向拉伸时，金刚石烯具有高于 0.17 的最大弹性应变。然后在坍塌之前经历进一步的塑性变形。然而，当沿之字形方向拉伸时，最大弹性应变高于 0.3，例如在 250 K 时为 0.318。应变超过临界值后，色带很快就会塌陷。因此，金刚石烯具有沿锯齿形方向的弹脆特性。这种出色的弹性对于金刚石烯在柔性设备中的应用具有重要意义。