▎ 摘　　要

Modifying the surface of MgMn2O4 by reduced graphene oxide (rGO) improved the electrical conductivity of the MgMn2O4/rGO composite more than that of the pristine MgMn2O4. In this study, the performance of the pristine MgMn2O4 and the MgMn2O4/rGO composite, as cathode materials, was investigated in magnesium-ion batteries (MIBs). Structural studies were performed by using various techniques. The morphology of the MgMn2O4 hollow spheres in the rGO substrate was confirmed by the results of FE-SEM and TEM. Raman spectroscopy and X-ray powder diffraction (XRD) also confirmed the successful synthesis and the desired structure. In addition, the electrochemical performance of the cathode active substance was investigated by utilizing different electro-chemical methods. The initial capacity of MgMn2O4 was approximately 120 mAh g(-1), which reduced to 92 mAh g(-1) following 100 cycles with the capacity loss of approximately 25%. In comparison, the initial capacity of the MgMn2O4/rGO composite was 305 mAh g(-1), which decreased to 290 mAh g(-1). Based on our results, incorpo-rating rGO improved the performance of the active ingredient.