Research progress in metal-oxide supported on graphene as catalysts in oxygen reduction reaction

Abstract

Catalysts have an essential effect on oxygen reduction reactions(ORR). In recent years, many efforts have been made to search high-performance non precious metal catalysts that can replace Pt metals. As one of the catalysts with excellent ORR catalytic activity, transition metal oxides have attracted extensive research due to their low cost and abundant reserves, which have great potential in the field of ORR catalysis. However, due to the poor conductivity of most transition metal oxides, which greatly hinders their catalytic activity, it is important to load them on suitable carriers to improve the performance of ORR. Graphene is widely used as support for its unique electronic properties, excellent electrical conductivity and other good physical and chemical properties. In this paper, the research progress of graphene-supported transition metal oxides as ORR electrocatalysts was reviewed. Primarily, the application, development and perspective of this type of ORR electrocatalysts were discussed from some perspectives, such as the classification of graphene support, the species of metal oxides, and preparation methods. In addition, the application and development of graphene-supported metal oxide catalyst in ORR were mentioned. Moreover, it was indicated that the main development direction of graphene-supported metal oxide as ORR catalysts should be focused on the heteroatom-doped graphene as carrier and composite metal oxide as active materials, and tend to reduce the energy consumption and period of preparation process, improve the performance of the catalysts, to achieve the purpose of cost reduction and efficiency.

Keywords

• orr
• catalyst
• transition metal oxide
• graphene