Azobenzene junctions between graphene and graphene oxide contacts: Optical reconfiguration for solution-processed fabrication of devices
Methods: Molecular mechanics, Molecular dynamics
In this master thesis, the hybrids of carbon nanomaterials - graphene (G) and graphene oxide (GO) with photochromic azobenzene will be studied. Azobenzene isomerizes, i. e. changes its configuration under UV light, going to the bent cis-state, and back to the flat trans-state under blue light. Both G and GO materials contribute to the green technologies .
The goal is to simulate reversible changes in the geometrical structure of the junction, immersed in water.
An illustration of “G-azo-GO” junctions and their response to the light irradiation: the reversible changes in thickness Δh of the layer (1), the GO restructuring (2), the changes in the water content at the SAM/GO interface (3), the conformational transitions in the flexible linkers or changes in tilting angles of the molecules in SAMs (4). Water molecules are omitted for clarity.
- To prepare the system shown in figure (parameters could be the molecular grafting density in the azobenzene layer, different oxidation degree of graphene oxide)
- To equilibrate the initial trans bilayer in molecular dynamics simulation
- To switch the isomerization state of azobenzene (parameter could be the isomers’ ratio) and equilibrate it
- To analyse both systems 2) and 3) prior and after isomerization. The properties to evaluate are: the overall morphology and stability, thickness Δh of the layer, the hydration of the azobenzenes (interface hydrophobicity), etc.
Key words: azobenzene, graphene, graphene oxide, junction, molecular dynamics, switching
Betreuer: Dr. Olga Guskova / IPF Dresden
 Min M., Seo S., Lee S.M., Lee H., Voltage-Controlled Nonvolatile Molecular Memory of an Azobenzene Monolayer through Solution-Processed Reduced Graphene Oxide Contacts, Adv. Mater., 2013, 25(48), 7045