Activated carbon aerogel containing graphene as electrode material for supercapacitor

Resorcinol-formaldehyde aerogel containing graphene oxide (RFGO) was prepared by a sol-gel polymerization of resorcinol with formaldehyde using polyethyleneimine (PEI)-modified graphene oxide, and activated carbon aerogel containing graphene (ACAG) was then prepared by a chemical activation with K2CO3. For comparison, graphene-free activated carbon aerogel (ACA) was prepared by the same method using graphene oxide-free resorcinol-formaldehyde aerogel. Non-activated carbon aerogel (CA) was also prepared. BET surface area and pore volume of ACA and ACAG were remarkably enhanced with well-developed porous structure compared to those of CA. Electrochemical performance of CA, ACA, and ACAG electrodes were measured by cyclic voltammetry and galvanostatic charge/discharge methods. ACAG showed higher specific capacitance than ACA with excellent supercapacitive behavior (300 F/g vs. 271 F/g). Equivalent series resistance (ESR) of ACAG (0.40 Omega) was smaller than that of ACA (0.57 Omega). The enhanced electrochemical performance of ACAG electrode was due to graphene layer of ACAG. (C) 2013 Elsevier Ltd. All rights reserved.