Oxygen-Vacancy-Abundant Ferrites on N-Doped Carbon Nanosheets as High-Performance Li-Ion Battery Anodes

Transition metal oxides, as one of the most promising anode materials for lithium-ion batteries, often suffer from poor electronic conductivity and serious structural collapse. In this work, oxygen-vacancy-abundant CoFe₂ O₄ and NiFe₂ O₄ deposited on N-doped carbon nanosheets are designed and fabricated through a calcination procedure and a solvothermal strategy using Zn-hexamine coordination frameworks as precursors. The as-prepared NC@CoFe₂ O₄ and NC@NiFe₂ O₄ hybrids display improved cycle performances and rate capacities compared with CoFe₂ O₄ , NiFe₂ O₄ , and Fe₂ O₃ . The enhanced lithium storage performances of NC@CoFe₂ O₄ and NC@NiFe₂ O₄ are attributed to the oxygen vacancies and conductive N-doped carbon nanosheets, which increase the electronic conductivity and electrochemical reaction kinetics. The synthetic process in this work provides a new perspective for designing other high-performance transition metal oxide anodes.