Di Giovannantonio Marco, Contini Giorgio
Empa, Swiss Federal Laboratories for Materials Science and Technology, Überlandstrasse 129, 8600 Dübendorf, Switzerland.
J Phys Condens Matter. 2018 Mar 7;30(9):093001. doi: 10.1088/1361-648X/aaa8cb.
Surface-confined polymerization is a bottom-up strategy to create one- and two-dimensional covalent organic nanostructures with a π-conjugated backbone, which are suitable to be employed in real-life electronic devices, due to their high mechanical resistance and electronic charge transport efficiency. This strategy makes it possible to change the properties of the final nanostructures by a careful choice of the monomer architecture (i.e. of its constituent atoms and their spatial arrangement). Several chemical reactions have been proven to form low-dimensional polymers on surfaces, exploiting a variety of precursors in combination with metal (e.g. Cu, Ag, Au) and insulating (e.g. NaCl, CaCO) surfaces. One of the main challenges of such an approach is to obtain nanostructures with long-range order, to boost the conductance performances of these materials. Most of the exploited chemical reactions use irreversible coupling between the monomers and, as a consequence, the resulting structures often suffer from poor order and high defect density. This review focuses on the state-of-the-art surface-confined polymerization reactions, with particular attention paid to reversible coupling pathways and irreversible processes including intermediate states, which are key aspects to control to increase the order of the final nanostructure.
表面受限聚合是一种自下而上的策略，用于创建具有π共轭主链的一维和二维共价有机纳米结构。由于其高机械抗性和电子电荷传输效率，这些纳米结构适用于实际的电子设备。这种策略使得通过仔细选择单体结构（即其组成原子及其空间排列）来改变最终纳米结构的性质成为可能。已经证明，利用多种前体与金属（如铜、银、金）和绝缘（如氯化钠、碳酸钙）表面相结合，通过几种化学反应可以在表面形成低维聚合物。这种方法的主要挑战之一是获得具有长程有序的纳米结构，以提高这些材料的导电性能。大多数利用的化学反应使用单体之间的不可逆偶联，因此，所得结构往往存在有序性差和缺陷密度高的问题。本综述重点关注了表面受限聚合反应的最新进展，特别关注可逆偶联途径和包括中间态在内的不可逆过程，这些是控制最终纳米结构有序性的关键方面。
