Abstract:
The increasing levels of atmospheric CO₂ from industrial activities necessitate effective technologies
to mitigate climate change. Electrochemical CO₂ reduction offers a promising route to convert CO₂ into
valuable products like formate, but challenges such as high overpotential, low selectivity, and catalyst
instability hinder its efficiency. Conventional catalysts, while effective, often suffer from low
performance or high costs, driving the search for alternative materials. This research explores
magnesium-manganese oxide-based catalysts on nickel foam, leveraging their synergistic effects,
unique structural properties, and cost-effectiveness to enhance Electrochemical CO2 reduction
efficiency. The catalysts were directly grown on nickel foam via immersion in a precursor solution
followed by calcination at 600°C. Structural and compositional analysis through X-ray diffraction (XRD),
scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) confirmed the
formation of crystalline phases, including Ni₆MnO₈, NiO, and NiMnO₃, with magnesium likely
incorporated into the manganese oxide lattice. SEM revealed coral reef-like morphology, while
elemental analysis indicated a uniform distribution of magnesium (1.1%) and manganese (22.1%)
within the porous nickel foam. The optimized catalyst, Mg1.1-Mn22.1-Ox/NiF, exhibited superior
electrocatalytic performance, achieving a high current density of -63.24 mA cm⁻² at -0.85 V vs. RHE and
a low onset potential of 0.07 V, indicating improved charge transfer capabilities. These findings
highlight the structural and compositional advantages of magnesium integration, significantly
enhancing catalytic activity and stability. This work provides valuable insights into the design of
advanced electrocatalysts for efficient CO₂ reduction, paving the way for further optimization and
exploration of magnesium-manganese-based oxides systems.
