Abstract Three-dimensional porous carbon materials play a significant role in gas separation and energy storage. However, their low performances in energy storage hamper their applications. Herein, we propose a new possible category of carbon honeycomb (CHC), i.e. CHCs with asymmetrical channels (denoted as asymmetrical CHCs), to increase their performance. As an example, by cross-linking graphene sheet with sp3–hybridized carbon chains, we prepare a new 3D porous asymmetrical CHC, i.e. bco-C24. It is dynamically, thermally, and mechanically stable. Our first-principles calculations and tight binding results demonstrate that it possesses a significant electronic band structure of Dirac nodal lines, which are ascribed to the px and py orbitals of α carbon atoms in the graphene ribbons that have both α and β carbon atoms. It provides high carrier mobility between 7.98 × 105 and 9.99 × 105 m/s. It has high theoretical capacities (743.8/495.9/991.8/743.8 mA h/g), low diffusion barriers (0.077/0.032/0.117/0.169 eV), low average voltages, and negligible volume changes for Na/K/Ca/Li-ion batteries. This study not only constructs a new concept of asymmetrical CHCs and provides a strategy of cross-linking graphene sheets to create its sample structures, but also suggests new carriers for ion storage in the superior next generation metal-ion battery anodes.

中文翻译：

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Bco-C24：用于高性能金属离子电池阳极的新型 3D Dirac 节点线半金属碳蜂窝

摘要 三维多孔碳材料在气体分离和储能方面发挥着重要作用。然而，它们在储能方面的低性能阻碍了它们的应用。在此，我们提出了一种新的可能的碳蜂窝 (CHC) 类别，即具有不对称通道的 CHC（表示为不对称 CHC），以提高其性能。例如，通过将石墨烯片与 sp3 杂化碳链交联，我们制备了一种新的 3D 多孔不对称 CHC，即 bco-C24。它具有动态、热和机械稳定性。我们的第一性原理计算和紧束缚结果表明，它具有显着的狄拉克节线电子能带结构，这归因于同时具有 α 和 β 碳原子的石墨烯带中 α 碳原子的 px 和 py 轨道。它提供 7.98 × 105 和 9.99 × 105 m/s 之间的高载流子迁移率。它具有高理论容量（743.8/495.9/991.8/743.8 mA h/g）、低扩散势垒（0.077/0.032/0.117/0.169 eV）、低平均电压以及Na/K/Ca/Li-的体积变化可忽略不计离子电池。这项研究不仅构建了不对称 CHC 的新概念，并提供了交联石墨烯片以创建其样品结构的策略，而且还提出了用于在下一代金属离子电池阳极中存储离子的新载体。