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 CoFe ₂ O ₄ and NiFe ₂ O ₄ 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@CoFe ₂ O ₄ and NC@NiFe ₂ O ₄ hybrids display improved cycle performances and rate capacities compared with CoFe ₂ O ₄ , NiFe ₂ O ₄ , and Fe ₂ O ₃ . The enhanced lithium storage performances of NC@CoFe ₂ O ₄ and NC@NiFe ₂ O ₄ 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.
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