Tuning Electrical Properties of Graphene with Different π-Stacking Organic Molecules

Tuning of the electrical properties of graphene and functionalized graphene is very important to its use in optoelectronic devices. In this work, we study the electrical properties of graphene and graphene with different pi-stacking organic molecules. The different pi-stacking organic molecules used in the present study were hemin, 1-amino 2-naphthol 4-sulfonic acid, and ferrocene. The noncovalently functionalized reduced graphene oxides were characterized by UV-visible spectroscopy, Fourier transformed infrared spectroscopy, atomic force microscopy, scanning electron microscopy, thermogravimetric analysis, and Raman spectroscopy. The noncovalently functionalized reduced graphene oxide show higher ac conductivity than graphene oxide (GO). The enhancement of conductivity shown can be attributed to higher mobility, and the density of pi-electron and higher surface area of hybrid nanocomposites system. The reason is supported because that interaction of rGO with non-pi-system like 18-crown-6 did not help in increasing the ac conductivity of the system. Thus, the electrical properties of graphene can be tuned through noncovalent interaction with pi-stacking organic molecules.