The application and research progress of hydrogen peroxide as cathode oxidant in fuel cells

With the continuous growth of global energy demand, issues related to energy security and environmental sustainability have attracted increasing attention. In recent decades, innovations in alternative energy technologies have significantly advanced the development of fuel cells as a promising clean energy solution. Traditional fuel cells utilize oxygen as the cathode oxidant; however, their application is limited in oxygen-deficient or anoxic environments. In contrast, hydrogen peroxide (H2O2), as a liquid oxidant, offers several advantages in terms of storage and transport, while also facilitating more direct reactions at the solid-liquid interface. Moreover, the two-electron reduction mechanism of H2O2 considerably enhances the reaction rate. This review summarizes the applications of H2O2 in fuel cells and highlights the research progress related to cathode catalysts. First, the use of H2O2 as a cathode oxidant in various types of fuel cells was explored. Second, the performance and challenges of precious metal catalysts, transition metal catalysts, and other catalysts in hydrogen peroxide reduction reactions (HPRR) are analyzed. Finally, the future research directions in this field are discussed.