Layer-by-layer self-assembly of graphene nanoplatelets.

In this report, graphene nanoplatelets were self-assembled through the layer-by-layer (LBL) method. The graphene surface was modified with poly(acrylic acid) and poly(acryl amide) by covalent bonding, which introduced negative and positive charge on the surface of graphene, respectively. Through electrostatic interaction, the positively and negatively charged graphene nanoplatelets assembled together to form a multilayer structure. Thermogravimetric analysis, Raman spectroscopy, scanning electron microscopy (SEM), and atomic force microscopy were used to demonstrate the modification of graphene nanoplatelets. Fourier transform infrared spectroscopy and SEM proved this method is feasible for preparing graphene-containing films. Ultraviolet-visible spectroscopy confirmed that the adsorption technique resulted in uniform film growth.