Carbon material with high specific surface area and high pseudocapacitance: Possible application in supercapacitors

Abstract

A new carbon material (NCM-R) was studied, which has a number of unique properties: a high specific surface area according to the BET (S BET = 3270 m 2 /g), a high micropore volume (~1.7 cm 3 /g), and a very high specific capacity of 870 F/g. The NCM-R is obtained by carbonizing a mixture of dextrin and graphene oxide and activating the carbonizate with potassium hydroxide. Based on the charging and discharge characteristics, it was established that the NCM-R is a promising material for supercapacitor electrodes with very small (diapason of a few seconds) discharge times and anodes of asymmetric supercapacitors with high specific energy. It is assumed that a large specific capacity is due to the reversible chemical attachment of hydrogen atoms to the carbon skeleton when the NCM-R charge is in the cathode region of the potentials. • Alkaline activation of a carbonized GO/dextrin mixture was used for obtaining of NCM-R. • NCM-R has a specific surface area 3270 m 2 /g following the BET method. • NCM-R has a high micropore volume (~1.7 cm 3 /g). • A specific capacitance of NCM-R (870 F/g) is due to the intercalation of hydrogen into the carbon skeleton. • The average specific capacitance of the double electric layer in NCM-R was only 210 F/g.