Study of Cathode Oxygen Reduction Reaction (ORR) Catalysts for Proton Exchange Membrane Fuel Cells (PEMFCs)

With the increasing depletion of non-renewable energy sources, more and more attention is being paid to the development of sustainable energy sources. The paper outlines the fundamental ideas behind oxygen reduction reaction (ORR) catalysts and proton exchange membrane fuel cells (PEMFCs), discusses the various types of ORR catalysts, and examines the limitations of this technology. In this paper, three types of ORR catalysts, metal catalysts, non-precious metal catalysts, and non-metal catalysts, are introduced in turn, and the pros and cons of the three types of ORR catalysts are analysed. Among them, metal catalysts possess advantages such as high efficiency and controllability, but are expensive and difficult to commercialise widely. The second type of catalyst is usually made from more common and cheaper metals and is therefore less expensive to produce. However, the catalytic activity is lower, resulting in a slower reaction rate and therefore a higher amount of catalyst is required. Non-metallic catalysts are usually not dependent on rare metal resources and are therefore relatively low cost. In addition, non-metallic catalysts offer higher selectivity and controllability, but lower catalytic rates. This paper expects that with the growth of the hydrogen energy industry, proton exchange membrane fuel cells will gradually be widely used in the fields of transport and power supply, providing a cleaner and more efficient energy source for human beings.