Metal–air batteries offer high energy density but suffer from sluggish oxygen electrochemistry. This work focuses on developing efficient bifunctional catalysts, combining NiFe-LDH with manganese-based materials, to address this challenge and enable the practical application of these promising energy-storage devices.
Manganese-based catalysts were synthesized via a sol–gel autocombustion method. NiFe-LDH materials were prepared through a hydrothermal method. The synthesized materials were subsequently compounded with pristine and nitrogen-doped carbon nanofibers to create composite electrodes. This combination aimed to improve the overall electrochemical performance of the materials. Electrochemical measurements were conducted in a conventional three-electrode cell configuration. An alkaline electrolyte was used, with a Hg/HgO electrode serving as the reference electrode and a graphite rod as the counter electrode. The electrocatalytic activity of the materials towards the ORR and OER was assessed through a series of electrochemical techniques, including cyclic voltammetry, linear sweep voltammetry, and electrochemical impedance spectroscopy.
Electrochemical evaluation using CV and LSV in a three-electrode cell revealed promising electrocatalytic activity of the synthesized NiFe-LDH and manganese-based materials towards both OER and ORR. The materials exhibited significant current densities and favorable onset potentials, consistent with their structural and compositional characteristics. These findings demonstrate their potential for high-performance metal–air battery applications.
This study demonstrates the feasibility of NiFe-LDH and manganese-based spinels as bifunctional electrocatalysts for metal–air batteries. A comprehensive characterization confirmed their desired properties, and an electrochemical evaluation revealed promising activity for both ORR and OER. While promising, further research is crucial to optimize their performance, including long-term stability studies and the exploration of strategies such as doping and support engineering. These findings contribute significantly to the advancement of sustainable energy technologies.
