Porphyrin Functionalized Graphene Sheets in Aqueous Suspensions: From the Preparation of Graphene Sheets to Highly Conductive Graphene Films

Abstract

Graphene has a unique structure and potential applications in nanoelectronics, nanocomposites, conductive and transparent films, etc. Synthesis of graphene is one of the major research efforts in order to make rapid developments in graphene research. In this study, a new method, that makes use of the π−π interactions between porphyrin and graphene to stabilize the chemically converted graphene (CCG), has been developed for preparation of CCG via chemical reduction of exfoliated graphene oxide (GO). Optical absorption spectroscopy measurement shows that π−π interactions take place between GO and porphyrins, 5,10,15,20-tetraphenyl-21H, 23H-porphine-p,p′,p′′,p′′′-tetrasulfonic acid tetrasodium hydrate (TPP-SO3Na) and 5,10,15,20-tetrakis(4-trimethylammoniophenyl) porphyrin tetra(p-toluenesulfonate). TPP-SO3Na functionalized CCG can form a stable aqueous suspension due to the electrostatic repulsion between the CCG sheets, which results from the aggregation of TPP-SO3Na molecules on the surfaces of the CCG she...