Faculty of Physics, University of Bielefeld, 33615 Bielefeld, Germany.
ACS Nano. 2013 Aug 27;7(8):6489-97. doi: 10.1021/nn402652f. Epub 2013 Jul 9.
Free-standing nanomembranes with molecular or atomic thickness are currently explored for separation technologies, electronics, and sensing. Their engineering with well-defined structural and functional properties is a challenge for materials research. Here we present a broadly applicable scheme to create mechanically stable carbon nanomembranes (CNMs) with a thickness of ~0.5 to ~3 nm. Monolayers of polyaromatic molecules (oligophenyls, hexaphenylbenzene, and polycyclic aromatic hydrocarbons) were assembled and exposed to electrons that cross-link them into CNMs; subsequent pyrolysis converts the CNMs into graphene sheets. In this transformation the thickness, porosity, and surface functionality of the nanomembranes are determined by the monolayers, and structural and functional features are passed on from the molecules through their monolayers to the CNMs and finally on to the graphene. Our procedure is scalable to large areas and allows the engineering of ultrathin nanomembranes by controlling the composition and structure of precursor molecules and their monolayers.
目前，具有分子或原子厚度的独立式纳米膜正在分离技术、电子学和传感领域得到探索。用具有明确定义的结构和功能特性来对其进行工程设计是材料研究的一个挑战。在这里，我们提出了一种广泛适用的方案，可制造厚度约为 0.5 至 3nm 的机械稳定的碳纳米膜（CNM）。通过组装单层多环芳烃分子（寡苯基、六苯并苯和多环芳烃），然后暴露于电子，使它们交联成 CNM；随后的热解将 CNM 转化为石墨烯片。在这种转变中，纳米膜的厚度、孔隙率和表面功能由单层决定，并且结构和功能特征通过其单层从分子传递到 CNM，最后传递到石墨烯。我们的方法可扩展到大面积，并通过控制前体分子及其单层的组成和结构来实现超薄纳米膜的工程设计。
