Chemistry and characterization of the graphene basal plane and edge for recognition tunneling

Biopolymer sequencing with graphene edge-based tunnel junctions has the potential to overcome current limitations with the third generation of sequencing based on biological nanopores. Detection of nucleotides via (recognition) tunneling with noble metal break junctions show promising results; however, the bulky nature and a range of physical and chemical instabilities of the electrodes prevent advancing toward long-read sequencing with single base-calling accuracy. Graphene edges as tunnel electrodes may overcome these limitations, with the possibility to reach true single-molecule readout, thanks to their 2D-nature. Currently, the development of graphene tunnel sequencers face challenges in terms of targeted chemical functionalization of the graphene edge, to enable recognition tunneling, and the eventual integration in a nanopore configuration to realize long-read sequencing of biopolymers. The dissertation tackles the possibility of achieving targeted chemical functionalization in a device architecture suitable for recognition tunneling and investigates the ability to characterize molecules attached on graphene through surface-enhanced Raman spectroscopy.<br>