In this work, three chemicals, including Aprepitant functionalized graphene oxide (APR-FGO), PhenmimCl ionic liquid (IL), and activated carbon derived from Satureja seed (AC-SS), were synthesized and used in a supercapacitor system as electrode materials. After the structural description of the synthesized materials, the electrochemical performance of APR-FGO, APR-FGO/AC-SS, and APR-FGO/AC-SS/IL electrodes was investigated in a three-electrode system. Based on the comparison of electrochemical results, the APR-FGO/AC-SS/IL electrode was able to provide the best performance compared to the other two electrodes. It was observed that the APR-FGO/AC-SS/IL electrode presented the specific capacitance (Cs) of 493.24 F g−1 at 1 A g−1. Also, the Cs retention value of the APR-FGO/AC-SS/IL electrode was 95.2 % at 8 A g−1 over 10,000 charge-discharge cycles. Furthermore, in a two-electrode system, the APR-FGO/AC-SS/IL electrode obtained a Cs of 214 F g−1, an energy density of 32.22 Wh kg−1, and a power density of 850 W kg−1 at 1 A g−1. These findings prove the ideal electrochemical performance of this composite as a supercapacitor electrode. The superior performance of the APR-FGO/AC-SS/IL electrode can be attributed to the presence of groups containing nitrogen and fluorine in the Aprepitant functionalized graphene oxide structure, the essential role of AC-SS as a substrate for performing electrochemical reactions, and the high conductivity of the PhenmimCl ionic liquid. Therefore, the proper synergy of these three materials shows that the APR-FGO/AC-SS/IL electrode has a high potential for energy storage systems.