Surface Modification of Nanocrystalline LiMn₂O₄ Using Graphene Oxide Flakes

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Lithium manganese oxide (LiMn2O4, LMO) is a promising cathode material for lithium-ion batteries.
• Improving the electrochemical stability and cycle life of LMO is critical for practical applications.
• Graphene oxide (GO) offers unique properties for material modification.

Purpose of the Study:

• To synthesize and characterize LiMn2O4/graphene oxide (LMO/GO) nanocomposites.
• To evaluate the electrochemical performance of LMO/GO as a cathode material for Li-ion batteries.
• To investigate the effect of graphene oxide incorporation on the stability and capacity retention of LMO.

Main Methods:

• Facile wet chemical synthesis of LMO/GO composites with varying GO content (1-5% wt.).
• Rietveld refinement for crystallite size estimation (18-27 nm).
• Electrochemical testing using CR2013 coin cells at room temperature (3.0-4.3 V).

Main Results:

• LMO/GO nanocomposites were successfully synthesized.
• Specific discharge capacity after 100 cycles was 84 mAh g-1 for LMO and 83 mAh g-1 for LMO/5%wt. GO.
• LMO modified with 5%wt. GO retained over 91% of its initial capacity, compared to 86% for pristine LMO.

Conclusions:

• Graphene oxide incorporation enhances the cycling stability of LiMn2O4 cathode materials.
• LMO/GO composites demonstrate improved long-term performance for Li-ion batteries.
• The study highlights the potential of LMO/GO nanocomposites for next-generation energy storage solutions.