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

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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.