Graphene Doped with Transition Metal Oxides: Enhancement of Anode Performance in Lithium-Ion Batteries
Jun Du, Liwei Liao, Binbin Jin, Xinyi Shen, Zhe Mei, Qingcheng Du, H. Nong, Bing‐Xin Lei, Liying Liang
Abstract
In recent years, transition metal oxides (TMOs) have emerged as promising candidates for anode materials in lithium-ion batteries (LIBs) owing to their high theoretical capacities. Regrettably, most TMOs exhibit poor electronic/ionic conductivity and undergo substantial volume expansion during the lithiation/delithiation processes. In this study, an electrostatic spinning method using polyacrylonitrile, graphene, and iron(III) acetylacetonate as precursors was employed to synthesize the Fe3O4@G/C composite through carbon coating and graphene doping. The composition, phase structure, and morphology of the Fe3O4@G/C composite were thoroughly investigated. The electrochemical performance of the Fe3O4@G/C composite as a lithium-ion battery anode was evaluated through a continuous charge–discharge cycling test. After 100 cycles at a current density of 0.1 A/g, the specific capacity of the Fe3O4@G/C material remained at 595.8 mAh/g. Additionally, the incorporation of graphene leads to a reduction in the electron orbital energy of Fe, which was verified by comparing the density of states (DOS) before and after the doping. Simultaneously, the electrochemical performance of CoO@G/C and NiO@G/C composites further demonstrates that doping transition metal oxides with graphene can enhance their performance as anodes for lithium-ion batteries. We anticipate that this design concept will open new avenues for the development of transition metal oxides (TMOs) and propel their adoption in practical applications.