Efficient iron-cobalt oxide bifunctional electrode catalysts in rechargeable high current density zinc-air batteries.

Iron-cobalt (FeCo) oxides dispersed on reduced graphene oxide (rGO) were synthesized from nitrate precursors at loading levels from 10 wt% to 60 wt%. These catalysts were tested in lab-scale zinc-air batteries (ZABs) at a high current density of 100 mA cm of the cathode area for the first time, cycling between 60 min of discharging and 60 min of charging. The optimum loading level for the best ZAB cycling performance was found to be 40 wt%, at which CoFeO and CoO nanocrystals were detected.