Two-dimensional (2D) Dirac cone materials have received wide attention for their advanced properties, such as nearly-zero effective masses and ultrahigh carrier mobility. However, the robust zero bandgap limited their applications in high-performance electronic devices. In this work, we proposed a series of new 2D Dirac cone materials, termed as g-AB${}_6$ monolayers (A = C, Si, and Ge; B = C, Si, Ge, and Sn). We found that the coexistence of $s{p}^2$ and $s{p}^3$ hybridization would heavily decrease the structural stability, hence the stable g-AB${}_6$ monolayers were only composed of $s{p}^2$ or $s{p}^3$ hybridized atoms. The electronic calculations revealed that all g-AB${}_6$ monolayers considered are 2D Dirac materials with linear energy dispersions near Fermi level, and they possess high Fermi velocities. Among them, the Fermi velocity of the g-SiC${}_6$ monolayer is up to 7.11 × 10${}^5\mathrm{m/s}$, which is the highest value among the known group IVA binary Dirac materials. Additionally, the Dirac cone of g-SiC${}_6$ monolayer could be modulated by applying moderate in-plane uniaxial or shear strains (<5%), which are much easier than that of graphene and silicene. Moreover, the g-SiC${}_6$, g-GeSi${}_6$, g-SiGe${}_6$, and g-GeSn${}_6$ monolayer have been identified with nontrivial $Z_2$ topological invariant ($Z_2$ = 1), and the g-GeSn${}_6$ monolayer was demonstrated as a room temperature topological insulator due to that spin–orbit coupling opens a large bandgap of 319 meV. Considering that the g-AB${}_6$ monolayers possess excellent dynamical, thermal, and mechanical stability, the g-AB${}_6$ monolayers are a promising candidate for realizing high-speed tunable electronic devices.

二维 (2D) Dirac 锥材料因其先进的性能而受到广泛关注，例如接近零的有效质量和超高的载流子迁移率。然而，强大的零带隙限制了它们在高性能电子设备中的应用。在这项工作中，我们提出了一系列新的二维狄拉克锥材料，称为 g-AB${}_6$单层（A = C、Si 和 Ge；B = C、Si、Ge 和 Sn）。我们发现共存$秒p^2$ 和 $秒p^3$ 杂交会严重降低结构稳定性，因此稳定的 g-AB${}_6$ 单层仅由 $秒p^2$ 或者 $秒p^3$杂化原子。电子计算表明所有 g-AB${}_6$考虑的单层是具有接近费米能级的线性能量色散的二维狄拉克材料，并且它们具有高费米速度。其中，g-SiC 的费米速度${}_6$ 单层高达 7.11 × 10${}^5\mathrm{多发性硬化症}$，这是已知 IVA 族二元狄拉克材料中的最高值。此外，g-SiC 的狄拉克锥${}_6$单层可以通过施加适度的面内单轴或剪切应变（<5%）来调节，这比石墨烯和硅烯容易得多。此外，g-SiC${}_6$, g-GeSi${}_6$, g-SiGe${}_6$, 和 g-GeSn${}_6$ 单层已被鉴定为非平凡 $Z_2$ 拓扑不变量（$Z_2$ = 1), 和 g-GeSn${}_6$由于自旋轨道耦合打开了 319 meV 的大带隙，单层被证明是室温拓扑绝缘体。考虑到 g-AB${}_6$ 单分子层具有优异的动态、热和机械稳定性，g-AB${}_6$ 单层是实现高速可调电子器件的有希望的候选者。