Jae-Jin Shim
Due to the increase in the use of unsteady renewable energy, energy storage has been an important issue worldwide. Due to the increase in the environmental pollution, decomposition technique and efficient catalysts are required to solve the problems. Materials based on carbon materials such as graphene, carbon nanotubes, and carbon fibers have been studied for capacitive energy storage. On the other hand, metal oxides or sulfides have been studied as catalysts and photocatalysts. Because their performances are limited, many attempts have been made to enhance their electrochemical properties by combining carbon materials with metal oxides or sulfides for both supercapacitors and catalysts applications. Due to their large surface area and high electrical conductivity, synergistic effects of excellent conductivities of graphene and high electrochemical properties of metal oxides or sulfides have improved the overall electrochemical performances tremendously. These composites show good electrochemical performances especially they are reduced to nano size. In this study, carbonaceous materials such as graphene, carbon nanotubes, carbon nano-onions and various mono-, binary-, and ternary-metal oxides or sulfides have been combined to make nanocomposites. Doping of sulfur or nitrogen has also been investigated to get higher performances.
