Anchoring FeCo2O4 nanoparticles on reduced graphene oxide: optimizing the loading effect for high-performance lithium-ion battery anodes

Co 3 O 4 exhibits a high theoretical specific capacity and excellent lithium storage performance, making it a promising lithium-ion battery anode. Nonetheless, its high cost, low intrinsic conductivity, and significant volume change during cycling hinder its widespread application. In this study, Co sites in the spinel Co 3 O 4 was partially substituted with eco-friendly and low-cost Fe to form the bimetallic oxide FeCo 2 O 4 . To enhance conductivity and stabilize the oxide material, reduced graphene oxide (RGO) was incorporated to serve as both a conductive matrix and a mechanical buffer, anchoring the FeCo 2 O 4 nanoparticles to mitigate volume expansion/contraction. The uniform dispersion of FeCo 2 O 4 nanoparticles loaded on the layered RGO architecture was achieved through a facile solvothermal method, effectively mitigating nanoparticle agglomeration and RGO restacking. This approach facilitated the orderly arrangement of FeCo 2 O 4 and enhanced the cycling stability of the electrode. Additionally, the high conductivity of RGO provided efficient pathways for ion and electron transport, further boosting the overall electrochemical performance of FeCo 2 O 4 . At an optimal FeCo 2 O 4 /RGO mass ratio of 10:1, the composite demonstrated an initial specific discharge capacity of 1092.4 mAh g − 1 at 0.5 C, significantly outperforming pure FeCo 2 O 4 (859.2 mAh g − 1 ) under the same conditions. The anchoring effect of RGO substantially enhanced the electrochemical performance of FeCo 2 O 4 . This work underscores the efficacy of synergistic composite design and provides a practical approach for developing advanced bimetallic oxide anodes for high-energy-density lithium-ion batteries.