Fabrication and characterization of atomically precise on-surface nanoarchitectures on coinage metals and graphene
On-surface self-assembly and on-surface synthesis are approaches to construct novel one- and two- dimensional materials from the bottom up. By careful selection of molecules, their symmetry and properties, along with a suitable substrate material (surface on which the molecules are deposited) and appropriate reaction conditions, many novel molecular nanostructures can be created with a variety of structural and electronic properties.
In his thesis, Koen Houtsma studied the growth and resulting structure of these molecular nanostructures, along with their electronic properties. He studied the same chiral molecule on a variety of substrates under different reaction conditions. Key findings were that the availability of adatoms (atoms that naturally lie on top of the substrate) and preferred adsorption sites of the molecules play an important role in the growth and the resulting structure of the molecular nanostructures.
Houtsma further found that the chirality of the resulting structure could in some cases be tuned based on the reaction conditions during synthesis. Additionally, he created a system of two-dimensional molecular networks on graphene on iridium, using linear molecules in combination with iron or cobalt atoms. It turned out that graphene provides a versatile platform for creating novel molecular structures that are not possible on other surfaces like coinage metals. This thesis contributes to advancing the understanding of molecular self-assembly and the development of tailored nanostructures for future technologies.