Noncovalent Functionalization Of Graphene

Graphene is a newly available conductive material ideally suited for forming well-defined interfaces with electroactive compounds. Aromatic moieties typically interact with the graphene surface to maximize Van der Waals interactions, predisposing most compounds to lie flat on its basal plane. A tripodal motif binds multivalently to graphene through three pyrene moieties and projects easily varied functionality away from the surface. The thermodynamic and kinetic binding parameters of a tripod bearing a redox-active Co(II) bisterpyridyl complex were investigated electrochemically. The complex binds strongly to graphene and forms monolayers with a molecular footprint of 2.3 nm2 and a [DELTA]Gads = -38.8 ± 0.2 kJ mol-1. Its monolayers are stable in fresh electrolyte for more than 12 h and desorb from graphene 1000 times more slowly than model compounds bearing a single aromatic binding group. Tripods with naphthalene or phenanthrene moieties also desorb more rapidly than those with pyrene, but reach greater monolayer densities. Noncovalent functionalization also allows assembled functionality to behave dynamically on the surface, afeature not observed in conventional self assembled monolayers. In addition, while biomacromolecuels adsorbed on bare graphene can lose their function, tripods bearing N-hydroxy succinimidyl ester groups immobilize both antibodies and Concanavalin A without loss of function. This result represents an important step forward in the design of flexible biosensors and provides a modular method for engineering the surface chemistry of graphene for biological applications.

Name thesis:degree_name

Ph. D., Chemistry and Chemical Biology

Level thesis:degree_level

Doctor of Philosophy

Discipline thesis:degree_discipline

Chemistry and Chemical Biology

Grantor

Cornell University

Year dc:date.issued

2013

Author dc:creator

• Mann, Jason

Committee members dc:contributor.committeemember

• Coates, Geoffrey
• Abruna, Hector D

• Synthesis
• self-assembly
• organic
• coordination
• biosensor
• analytical
• QCM
• electrochemistry
• noncovalent
• graphene

Language dc:language.iso

en_US

Handle dc:identifier.uri

https://hdl.handle.net/1813/34257

OAI identifier oai:identifier

oai:ecommons.cornell.edu:1813/34257