Selection of Catalysts for Oxygen Reduction in Proton Exchange

Nowadays, the energy crisis is becoming more and more severe, and using fossil fuels widely has caused a large number of environmental problems, with the most severe impact being the greenhouse effect. At the same time, the problem of glacier melting has also been affecting our daily lives. In addition to the loss of habitat for a large number of animals and the impact on freshwater resources, the melting of glaciers is detrimental to the health of the human diet, among other issues. Due to their products' high energy density and lack of pollutants, hydrogen fuel cells have attracted a lot of interest. One of the main obstacles in the development of hydrogen fuel cells, while there are still many others as well, is the catalyst for the oxygen reduction process, which takes place in the cathode section of the hydrogen fuel cell's energy conversion core. Because the cathode oxygen reduction process is inactive and moves slowly, proton exchange membrane fuel cells (PEMFC) need to utilize a catalyst to speed up the reaction and increase efficiency even more. Proton exchange fuel cell catalysts may be broadly categorized into three groups: non-metal, non-precious metal, and precious metal catalysts. This article primarily examines, with examples, the benefits and drawbacks of several kinds of catalysts. In the review's conclusion, also discusses the challenges to their future development and the possibilities for PEMFC catalysts.