Rational design, synthesis and characterization of surface-confined low-dimensional nanomaterials

人们对低维材料的兴趣与日俱增，原因在于它们因降维而产生的高导电性、高传热性、机械稳定性和化学稳定性等优异性能。这些特殊的性质标志着石墨烯，自然界中唯一的2D(片状)材料，成为过去十年的转折点材料。然而，缺少电子带隙可能会限制其在某些电子应用中的使用。这种局限性激发了新型低维纳米材料的出现，如2D聚合物和共价有机骨架--构成了石墨烯的主要有机类似物。这些材料的化学和电子性质是由它们的形态、尺寸、大小、对其构件的仔细选择、它们的p电子离域以及将它们连接在一起的键的化学性质决定的。目前的计划建立在纳米科学技术的基础上，以合成表面受限的2D聚合物，其化学和电子性能可以通过其化学结构来定制。提出了几种表面受限聚合和缩合反应来合成分子基低维纳米材料，包括二维聚酰胺、二维共轭多孔聚合物、共价有机骨架。为了鉴定它们的形貌和化学性质，将具有原子尺度分辨率的扫描隧道显微镜与X射线光电子能谱和密度泛函理论计算相结合。开发低维纳米材料提供了基础知识，对加拿大相应的技术进步具有重大好处。多孔2D聚合物为环境应用提供了吸附和储存温室气体的化学成分和结构体系。2D聚合物的化学稳定性、热稳定性和机械稳定性使其有望成为飞机和轨道交通行业中用作保护表面的候选材料。从半导体到绝缘行为的电子特性使其适用于电子行业，例如在高电压下运行的热电半导体，以及用于收集能量和光。总之，拟议的研究为基于分子的低维纳米材料的受控结构提供了一个平台，该材料具有从半导体到绝缘性能的定制，并在恶劣条件下提高了稳定性。这些纳米材料提供独特的电子性能，使其在用于显示器、智能手机、传感器和太阳能电池的有机电子设备中得到应用。

The growing interest in low-dimensional materials stems from their remarkable properties, such as high electrical conductivity, heat transfer, mechanical and chemical stability, arising from dimension reduction. These exceptional properties mark graphene, the only 2D (sheet) material in nature, as the turning point material of the last decade. However, the lack of an electronic bandgap can limit its use in some electronic applications. This limitation has inspired the emergence of novel low-dimensional nanomaterials such as 2D polymers and covalent organic frameworks - to constitute prominent classes of organic analogues of graphene. The chemical and electronic properties of these materials are determined by their morphology, dimension, size, a careful choice of their building blocks, their p-electron delocalization, and the chemical nature of the bonds held them together. The present program builds on the nanoscience techniques to synthesize surface-confined 2D polymers whose chemical and electronic properties can be tailored by their chemical structure. Several surface-confined polymerization and condensation reactions are proposed for the synthesis of molecular-based low-dimensional nanomaterials including 2D polyamides, 2D conjugated porous polymers, covalent organic frameworks. To identify their morphology and chemical nature, scanning tunnelling microscopy with atomic scale resolution, will be combined with X-ray photoelectron spectroscopy and density functional theory calculations. Developing low-dimensional nanomaterials provides fundamental knowledge with significant benefits to the corresponding technological advances in Canada. Porous 2D polymers offer the chemical compositions and structural architectures for the adsorption and storage of greenhouse gases for environmental applications. The chemical, thermal, and mechanical stability of 2D polymers make them promising candidates to be implemented as protective surfaces in the aircraft and rail transportation industries. Electronic properties, ranging from semiconducting to insulating behaviour, make them suitable for electronics industries, as for example thermoelectric semiconductors performing at elevated voltages, as well as for harvesting energy and light. In summary, the proposed research offers a platform for the controlled architecture of molecular-based low-dimensional nanomaterials, tailored with semiconducting to insulating properties, and an elevated stability under harsh conditions. These nanomaterials provide unique electronic properties, giving rise to applications in organic electronic devices used in displays, smartphones, sensors, and solar cells.