Global warming is rapidly becoming a major concern as a result of the continuing emissions of greenhouse gases generated by the combustion of fossil fuels. To resolve this problem, various studies on efficient energy storage devices have been undertaken. Electronic technologies are increasingly used in electronic products and systems, and they require effective energy storage [1,2]. Supercapacitors are energy storage devices with high power density and long cycle life, and have been spotlighted in recent years because of their promising applications in portable devices, electric vehicles, transportation systems, digital devices.