Investigation of Oxygen Reduction Activity of Catalysts Derived from Co and Co/Zn Methyl-Imidazolate Frameworks in Proton Exchange Membrane Fuel Cells

We demonstrated that the oxygen reduction reaction (ORR) activity over catalysts derived from pyrolyzed cobalt zeolitic imidazolate frameworks (ZIFs) depends strongly on the imidazole ligand structure and cobalt content. The activity and durability of these catalysts were tested in the proton exchange membrane fuel cell for the first time. The membrane electrode assembly containing a catalyst derived from Co/Zn bimetallic ZIF at the cathode achieved an open‐circuit voltage of 0.93 V, a current density of 28 mA cm−2 at 0.8 ViR‐free, and a peak power density of 374 mW cm−2. Smooth operator: The catalytic oxygen reduction reaction activity and durability of nonprecious‐metal catalysts derived from cobalt‐based monometallic and bimetallic zeolitic imidazolate frameworks are found to be strongly influenced by the imidazole ligand structure and cobalt concentration, as demonstrated by the fuel cell tests under operating conditions.