(Invited) Electrochemical Production of Graphene and Controlled Assembly of 3D Graphene Electrodes for Energy Storage Applications

Abstract

Graphene has been intensively studied for electrode material for electrochemical energy storage devices utilizing its high electrical conductivity and high surface area. Recently introduced electrochemical exfoliation process has many advantages over conventional chemical methods, including low-cost, simple operation, fast production-rate, and in-situ functionalization. In particular, anodic electrochemical exfoliation process is one of the promising methods for fast and simple production of graphene at low cost.In this presentation, we will first discuss the detailed mechanisms of the electrochemical exfoliation process of graphite into graphene using sulfate containing electrolyte systems. We systematically monitored the structural changes in graphite and associated gas formation during the electrochemical exfoliation process, revealing that water molecules are the main source of gaseous species for the effective exfoliation of graphite into graphene. Next, we will introduce our recent efforts to fabricate 3D structured graphene anodes for Li-, Na-, K-ion batteries. Moreover, we evaluated the temperature-dependent performance of 3D graphene anodes, demonstrating their superior charge storage performance in extreme cold environments.