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

The transition metal oxides as one of 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 calcinations procedure and a solvothermal strategy using Zn-hexamine coordination frameworks as precursor. 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 that increase the electronic conductivity and electrochemical reaction kinetics. This synthetic process in this work provides a new perspective in designing other transition metal oxides anodes with high-performance.