The development of multifunctional two-dimensional (2D) carbon-based materials with novel, excellent properties and high performance is a challenge. By using density functional theory methods, a novel 2D planar and porous carbon material 2D-C₁₈H₆, which is a poly-triphenylene membrane composed of triphenylene molecules, is systematically investigated. The computational results confirm that the 2D-C₁₈H₆ structure has good lattice dynamics stability and high thermal stability. 2D-C₁₈H₆ displays great gas separation ability with high selectivity and high diffusive flux of He and H₂ from other gas molecules, due to its dense pores of proper size in the structure. It is a semiconductor with a direct band gap of 2.36 eV and ultra-high carrier mobilities along both a and b directions, up to 7.6×10⁴ cm²V^-1s^-1. The adsorption and migration of K atoms on 2D-C₁₈H₆ monolayer indicate it exhibits ultra-high theoretical specific capacity of 1449 mAh·g^-1, low voltage of 0.285-0.024 V and low migration barrier of 0.125 eV. Possessing various excellent properties, 2D-C₁₈H₆ monolayer has potential applications in electronic device semiconductors, potassium ion battery anode materials, photocatalytic hydrogen evolution materials and gas separation membranes.

开发具有新颖、优异性能和高性能的多功能二维 (2D) 碳基材料是一项挑战。采用密度泛函理论方法，系统地研究了一种新型二维平面多孔碳材料2D-C ₁₈ H ₆，它是由苯并菲分子组成的聚苯并菲膜。计算结果证实2D-C ₁₈ H ₆结构具有良好的晶格动力学稳定性和高热稳定性。2D-C ₁₈ H ₆具有很强的气体分离能力，对He和H _{2具有高选择性和高扩散通量}来自其他气体分子，由于其结构中适当大小的致密孔隙。它是一种直接带隙为 2.36 eV 且沿a和b方向载流子迁移率高达 7.6×10 ⁴ cm ² V ^-1 s ^-1的超高载流子迁移率的半导体。_{K原子在2D-C 18} H ₆单分子层上的吸附和迁移表明其具有1449 mAh·g ^-1的超高理论比容量、0.285-0.024 V的低电压和0.125 eV的低迁移势垒。具有多种优良性能，2D-C ₁₈ H ₆单分子层在电子器件半导体、钾离子电池负极材料、光催化析氢材料和气体分离膜等方面具有潜在应用。