“…7 However, a fundamental obstacle impeding the practical implementation of ZABs is the high overpotential of the oxygen reduction reaction (ORR) and the oxygen evolution reaction (OER), which results in slow kinetics in the air cathode. [8][9][10][11][12] For obtaining better performance and durability for ZABs, noble metal catalysts (e.g., Pt, Ru, Ir) are usually applied to ZABs for the process of the ORR/OER. However, due to the limited resources and the high price of these noble metal catalysts, the cost of ZABs will remain higher while applying noble metal catalysts in ZABs.…”