Electrochemical Performance of Activated Graphene-Based Materials for Electrodes of Double-Layer Supercapacitors

Activated graphene oxide seems to be a promising electrode material for electrochemical double-layer capacitors, also known as supercapacitors or ultracapacitors, and other energy storage purposes. This article summarizes the results of our research about the effect of graphene oxide KOH-catalyzed activation on their specific surface area (SSA) and their capacitance, both strongly related to their electrochemical performance. KOH-catalyzed activation increased the SSA values of the reduced graphene oxide (rGO) from ∼783 m² g⁻¹ to ∼2144 m² g⁻¹; it is important to note that the SSA and oxygen-containing groups are two important factors determining electrochemical performance. Moreover, the highest capacitance value was 50.08 F g⁻¹, using 1.0 M H₂SO₄ as an aqueous electrolyte. Activated graphene-based materials with high SSA support conductive networks decorated with oxygen groups synergistically improve charge storage capability in EDLCs.