Designing 2D covalent networks with lattice Monte Carlo simulations: precursor self-assembly

Area of Science:

• Heterogeneous catalysis and material engineering
• Surface science and nanotechnology
• Computational chemistry and materials modeling

Background:

• Organic synthesis reactions in the adsorbed phase are crucial for heterogeneous catalysis and material engineering.
• Ullmann coupling is a key process for transforming halogenated monomers into polymeric structures.
• On-surface self-assembly offers a pathway to construct ordered 2D materials.

Purpose of the Study:

• To investigate the on-surface self-assembly of organometallic precursors with varied halogen substitution patterns.
• To explore the influence of intramolecular substituent distribution on the morphology of 2D superstructures.
• To analyze the formation of porous networks and the impact of prochiral building blocks on assembly.

Main Methods:

• Utilized lattice Monte Carlo simulations with a coarse-grained approach.
• Modeled molecules and metal atoms as discrete segments on a triangular lattice representing a (111) metallic surface.
• Performed simulations for enantiopure and racemic systems to analyze structural properties.

Main Results:

• Demonstrated that intramolecular halogen distribution significantly impacts superstructure morphology.
• Successfully directed self-assembly towards ordered porous networks with tunable pore characteristics.
• Showcased the ability to control pore shape and size in the resulting 2D covalent structures.

Conclusions:

• On-surface self-assembly of organometallic precursors provides a route to engineer 2D materials with designed architectures.
• Controllable pore size and shape in covalently bonded superstructures can be achieved by manipulating molecular design.
• These findings are valuable for the rational design of functional 2D materials for various applications.