ISTM-CNR, UdR INSTM and Department of Chemistry, University of Perugia, Perugia, 06123, Italy.
Nanoscale. 2012 Jan 21;4(2):369-79. doi: 10.1039/c1nr11112d. Epub 2011 Dec 14.
Low-dimensional carbon nanostructures, such as nanotubes and graphenes, represent one of the most promising classes of materials, in view of their potential use in nanotechnology. However, their exploitation in applications is often hindered by difficulties in their synthesis and purification. Despite the huge efforts by the research community, the production of nanostructured carbon materials with controlled properties is still beyond reach. Nonetheless, this step is nowadays mandatory for significant progresses in the realization of advanced applications and devices based on low-dimensional carbon nanostructures. Although promising alternative routes for the fabrication of nanostructured carbon materials have recently been proposed, a comprehensive understanding of the key factors governing the bottom-up assembly of simple precursors to form complex systems with tailored properties is still at its early stages. In this paper, following a survey of recent experimental efforts in the bottom-up synthesis of carbon nanostructures, we attempt to clarify generalized criteria for the design of suitable precursors that can be used as building blocks in the production of complex systems based on sp(2) carbon atoms and discuss potential synthetic strategies. In particular, the approaches presented in this feature article are based on the application of concepts borrowed from traditional organic chemistry, such as valence-bond theory and Clar sextet theory, and on their extension to the case of complex carbon nanomaterials. We also present and discuss a validation of these approaches through first-principle calculations on prototypical systems. Detailed studies on the processes involved in the bottom-up fabrication of low-dimensional carbon nanostructures are expected to pave the way for the design and optimization of precursors and efficient synthetic routes, thus allowing the development of novel materials with controlled morphology and properties that can be used in technological applications.
低维碳纳米结构，如纳米管和石墨烯，是最有前途的材料之一，因为它们在纳米技术中有潜在的应用。然而，它们在应用中的开发常常受到其合成和纯化的困难的阻碍。尽管研究界付出了巨大的努力，但具有可控性质的纳米结构碳材料的生产仍然难以实现。尽管如此，对于在基于低维碳纳米结构的先进应用和设备的实现方面取得重大进展，这一步骤是现在必不可少的。虽然最近已经提出了制造纳米结构碳材料的有前途的替代途径，但对于控制简单前体制备复杂系统的关键因素的综合理解仍处于早期阶段，这些系统具有定制的性质。在本文中，在对碳纳米结构的自下而上合成的最近实验努力进行调查之后，我们试图阐明用于设计合适前体的一般化标准，这些前体可用作基于 sp(2)碳原子的复杂系统生产中的构建块，并讨论潜在的合成策略。特别是，本文提出的方法基于从传统有机化学中借用的概念，例如价键理论和 Clar sextet 理论，以及将其扩展到复杂碳纳米材料的情况。我们还通过对原型系统的第一性原理计算来呈现和讨论这些方法的验证。对低维碳纳米结构自下而上制造过程的详细研究有望为前体和有效合成途径的设计和优化铺平道路，从而开发出具有可控形态和性能的新型材料，可用于技术应用。
