Electrochemical Exfoliation a Green Approach: Waste to Wealth

Graphene discovery in 2004 by Geim and co-workers was a major breakthrough in the field of material sciences. The creditability of graphene, which is a closely packed honeycomb two-dimensional lattice, owes to its exceptional electrical, mechanical and thermal properties. The applicability of this unique compound includes different devices for storing energy, causing conversion, generating proficient-performance composites, electronics at molecular level, field-emission, etc. That is why it has been attracting the attention of researchers since the beginning. Earlier, mechanical and chemical exfoliation was used for the preparation of graphene, but the process had a few loopholes which cannot be ignored. The problems range from high costs and environmental hazards to the production of toxic gases. To overcome these, recently new techniques came into picture like dry ball milling, electrochemical exfoliation, ultrasonication. However, out of many, electrochemical exfoliation is considered as a green, safe and substrate-free approach for graphene synthesis. It involves the usage of raw materials like pencil core, graphene pellets, graphene rods, palm oil leaf extract, etc. Therefore, the approach leads to the usage of waste or less important raw materials for more usable ones. In this chapter, different aspects of the electrochemical exfoliation process are highlighted with special reference to its green approach.