(705b) Dendritic (Snow-Flake-Shaped) Gold-Nanostructures Templated On Graphene: Tuning Electrical Properties and Raman Spectra

Being structurally distinct from 0D-molecules and 1D-polymers, solvent-dispersed graphene-chemical-derivatives (GCD) with quasi-2D structure behave as chemically active and atomically-thick substrates ?swimming' in solution. In this talk, we show that by controlling the rate of diffusion and catalytic reduction of gold ions on graphene-oxide, ?snow-flake-shaped' dendritic gold-nanostructures (SFGNs) can be templated on graphene. By utilizing the unique properties of anisotropic gold nanostructures (such as localized surface plasmon resonance, surface enhanced fluorescence) and graphene sheets (2-D construct, fermionic confinement, modifiable surface-chemistry) novel-graphene hybrids can be fabricated with applications in nanoelectronics, sensors, bio-imaging, opto-electronics and catalysis. Specifically, we will show that gold-attachment to graphene-oxide induces an electronic modification which can tune its electrical properties (band-gap, Schottky barrier, carrier mobility) and enhance its Raman signal. Further, the surface coverage of SFGNs can be controlled by modifying the gold diffusion rates on the surface of GCD sheets. We envision that the unique ability of graphene derivatives to be chemically modified/interfaced while being stably dispersed in solvents, will lead to their applications as ?floating-platforms' for mass-transfer controlled incorporation/crystallization of metals and molecules to build next generation graphene systems and composites with a multitude of applications in nano/opto electronics and several industrially relevant reactions such as catalysis, fuel-cell technology and pollution control.