Electrochemically functional graphene nanostructure and layer-by-layer nanocomposite incorporating adsorption of electroactive methylene blue

This paper describes preparation and characterization of electrochemically functional graphene nanostructure incorporating adsorption of electroactive methylene blue (MB) dye onto graphene and nanocomposite assembled using layer-by-layer of graphene with MB on solid substrates. UV–visible spectroscopy, FT-IR spectroscopy, Raman spectroscopy and electrochemistry for systematical characterization of the MB adsorption onto graphene reveal the formation of a MB/graphene adsorptive nanostructure through π–π stacking and hydrophobic interactions. Compared with MB adsorbed onto a graphene oxide (GO) modified electrode and MB adsorbed onto a GC electrode, MB adsorbed onto a graphene modified electrode exhibits a good stability and distinct electrochemical properties. Additionally, MB adsorbed onto graphene can improve the water-disperse ability of graphene. Furthermore, scanning electron microscopy, UV–vis-NIR spectroscopy and electrochemistry demonstrated that directly layer-by-layer assembling of MB and graphene was an excellent route to prepare a functional nanocomposite on different solid substrates including silica plate, quartz slide and glassy carbon electrode. The excellent electroactivity and the high stability of electrochemically functional graphene nanostructure and the layered nanocomposite are envisaged to make them very useful electrochemically functional nanomaterials for practical development of electronic devices such as biosensors and photovoltaic cells.