Abstract A computational finite element analysis based on a structural molecular mechanics approach was conducted to predict effective coefficients of thermal expansion (CTE) of a novel three-dimensional carbon nanostructure, pillared graphene structure (PGS), which is constituted with several graphene sheets and single-walled carbon nanotubes. Four sets of representative unitcell models were developed atomistically having different geometric parameters of pillar length and inter-pillar distance in the PGS. Periodic boundary conditions were applied to periodic unitcell geometries to yield consistent results. Parametric study shows that both pillar length and inter-pillar distance significantly affect the effective in-plane and through-thickness CTEs. The PGS with smaller inter-pillar distance and larger pillar length yields higher in-plane CTEs, while that with larger inter-pillar distance and smaller pillar length yields higher through-thickness CTE. The calculation yields negative through-thickness CTE at low temperatures ( T 100 K) for all sets of PGSs, which is associated with the curvature at the junction.

中文翻译：

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3-D CNT-石墨烯连接碳纳米结构热膨胀系数的量化预测

摘要 进行了基于结构分子力学方法的计算有限元分析，以预测新型三维碳纳米结构柱状石墨烯结构 (PGS) 的有效热膨胀系数 (CTE)，该结构由多个石墨烯片和单个石墨烯构成。 -壁碳纳米管。在 PGS 中，以原子方式开发了四组具有代表性的晶胞模型，它们具有不同的柱长和柱间距离几何参数。周期性边界条件应用于周期性晶胞几何结构以产生一致的结果。参数研究表明，支柱长度和支柱间距离都显着影响了有效的面内和全厚度 CTE。具有较小柱间距离和较大柱长的 PGS 产生更高的面内 CTE，而具有较大的柱间距离和较小的柱长会产生更高的全厚度 CTE。对于所有组 PGS，计算得出低温 (T 100 K) 下的负全厚度 CTE，这与结处的曲率有关。