Alves Rodrigo A F, L Lima Kleuton A, da Silva Daniel A, Mendonça Fábio L L, Ribeiro Junior Luiz A, Pereira Junior Marcelo L
Institute of Physics, University of Brasília, Brasília 70910900, Federal District, Brazil.
Computational Materials Laboratory, LCCMat, Institute of Physics, University of Brasília, Brasília 70910900, Federal District, Brazil.
ACS Omega. 2025 Apr 23;10(17):17159-17169. doi: 10.1021/acsomega.4c07524. eCollection 2025 May 6.
The interest in two-dimensional (2D) carbon allotropes arises from their ability to alter their properties based on the atomic topology employed, which can significantly affect their electronic properties and benefit advancements in new technologies. This work presents a new nanoporous graphene (NPG) allotrope obtained through lateral heterojunctions via pairs of trivalent sp carbon atoms of armchair graphene nanoribbons (AGNRs). These pairs were used as linkers between AGNRs to achieve this structure, forming connections that enhance the porous architecture. This novel planar and porous 2D carbon allotrope integrates some structural and electronic advantages of AGNRs into a 2D framework. Composed of 3-, 6-, and 12-membered carbon rings, the NPG was investigated using density functional theory (DFT) calculations and ab initio (AIMD) and classical molecular dynamics (CMD) simulations to explore its structural, electronic, and mechanical properties. Among the results presented, we show that the material demonstrates high dynamical and thermal stability at 1000 K. Furthermore, the NPG exhibits metallic and nonmagnetic behavior and is achieved by transitioning from the semiconducting nature of some AGNRs to a metallic 2D carbon system. The elastic properties reveal the material's distinct response to applied strain, with fractures occurring in the nanoribbon segment along the -direction. However, fractures are observed in the C-C bonds involved in the heterojunction region in the -direction. The calculated Young's modulus ranges from 394 to 690 GPa, which is lower but comparable to graphene. The formation energy of NPG decreases with increasing width of the AGNRs used to compose the 2D material, indicating enhanced stability for wider nanoribbons. These findings highlight the potential of NPG for applications in nanoelectronics and advanced new technologies.
对二维（2D）碳同素异形体的兴趣源于它们能够根据所采用的原子拓扑结构改变其性质，这会显著影响其电子性质并有利于新技术的进步。这项工作展示了一种通过扶手椅型石墨烯纳米带（AGNRs）的三价sp碳原子对形成的横向异质结获得的新型纳米多孔石墨烯（NPG）同素异形体。这些原子对被用作AGNRs之间的连接体以实现这种结构，形成增强多孔结构的连接。这种新型的平面多孔二维碳同素异形体将AGNRs的一些结构和电子优势整合到一个二维框架中。由3元、6元和12元碳环组成的NPG，使用密度泛函理论（DFT）计算以及从头算（AIMD）和经典分子动力学（CMD）模拟进行研究，以探索其结构、电子和力学性质。在给出的结果中，我们表明该材料在1000 K时表现出高动态和热稳定性。此外，NPG表现出金属性和非磁性行为，是通过从一些AGNRs的半导体性质转变为金属二维碳系统实现的。弹性性质揭示了材料对施加应变的独特响应，在沿 - 方向的纳米带段会发生断裂。然而，在 - 方向的异质结区域涉及的C - C键中观察到断裂。计算得到的杨氏模量范围为394至690 GPa，低于但与石墨烯相当。NPG的形成能随着用于构成二维材料的AGNRs宽度增加而降低，表明更宽的纳米带具有更高的稳定性。这些发现突出了NPG在纳米电子学和先进新技术中的应用潜力。
