Synthesis of graphene through electrochemical exfoliation technique in aqueous medium

Abstract

Abstract Graphene is just single layer of carbon atom compactly bound in hexagonal honeycomb lattice. Graphene is the component of different allotropes of carbon like CNT, graphite, diamond, charcoal and fullerene. In graphene the bonding orbital is Sp2 hybridized using only three out of the four valence electrons of carbon. The well-known 3-D graphitic crystal is formed by stacking graphene layers on top of one another. Its prominent physical, electronic as well as mechanical properties originate from the two-dimensional (2D) electronic confinement within the one-atom-thick layer. Graphene was fabricated by electrochemical exfoliation method in an aqueous medium. The electrolytic bath contains 0.1 M ferrous sulfate (FeSO4). Two high purity graphite rods, placed parallel to each other with a separation of 2.0 cm, were inserted as electrodes into solution of water and a consistent potential about 15–20 V was applied between the two graphite rods. Different characterization methods were used to evaluate the presence of graphene. The exfoliated graphene (EG) showed a diffraction peak at 2θ = 26.4°with (0 0 2) plane with intensity much less than that of graphite. The absorption peak of graphene appeared at 267 nm which is recognized to π-π* transition of C-O bonds due to the exfoliation and the intercalation on graphene. The photoluminescence (PL) peak was observed at 418 nm. The surface morphology shows the wrinkled paper-like appearance which is the characteristic of graphene.