Synthesis and superior cathode performance of sandwiched LiMn₂O₄@rGO nanocomposites for lithium-ion batteries

Spinel LiMn₂O₄ nanoparticles (NPs)loaded on reduced graphene oxide are prepared via a facile one-pot solvothermal method. The samples are characterized by transmission electron microscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, and thermogravimetry analysis. The resultant LiMn₂O₄-reduced graphene oxide nanocomposites material shows better performances as cathode for lithium-ion batteries than pure LiMn₂O₄ or physical mixing of LiMn₂O₄ and reduced graphene oxide. The LiMn₂O₄-reduced graphene oxide retains about 110 mAh g⁻¹ at 0.5 C after 150 cycles, indicating a better cycling stability than pure LiMn₂O₄ electrode. The resistance of the LiMn₂O₄-reduced graphene oxide nanocomposite cell presents great reduction due to the existence of reduced graphene oxide. The wrapping of reduced graphene oxide on LiMn₂O₄ NPs provides a few-layer conduct fishnet structure, which can greatly shorten the electron transfer path. This work shows the potential applications of the LiMn₂O₄-reduced graphene oxide as cathode material for high-power lithium-ion batteries.