Zinc–Air Battery: Understanding the Structure and Morphology Changes of Graphene-Supported CoMn2O4 Bifunctional Catalysts Under Practical Rechargeable Conditions

Nitrogen-doped/undoped thermally reduced graphene oxide (N-rGO) decorated with CoMn2O4 (CMO) nanoparticles were synthesized using a simple one-step hydrothermal method. The activity and stability of this hybrid catalyst were evaluated by preparing air electrodes with both primary and rechargeable zinc–air batteries that consume ambient air. Further, we investigated the relationship between the physical properties and the electrochemical results for hybrid electrodes at various cycles using X-ray diffraction, scanning electron microscopy, galvanodynamic charge–discharging and electrochemical impedance spectroscopy. The structural, morphological and electrocatalytic performances confirm that CMO/N-rGO is a promising material for safe, reliable, and long-lasting air cathodes for both primary and rechargeable zinc–air batteries that consume air under ambient condition.