A Facile Molten‐Salt Route for Large‐Scale Synthesis of NiFe 2 O 4 Nanoplates with Enhanced Lithium Storage Capability

Binary metal oxides have been deemed as a promising class of electrode materials for high‐performance lithium ion batteries owing to their higher conductivity and electrochemical activity than corresponding monometal oxides. Here, NiFe 2 O 4 nanoplates consisting of nanosized building blocks have been successfully fabricated by a facile, large‐scale NaCl and KCl molten‐salt route, and the changes in the morphology of NiFe 2 O 4 as a function of the molten‐salt amount have been systemically investigated. The results indicate that the molten‐salt amount mainly influences the diameter and thickness of the NiFe 2 O 4 nanoplates as well as the morphology of the nanosized building blocks. Cyclic voltammetry (CV) and galvanostatic charge–discharge measurements have been conducted to evaluate the lithium storage properties of the NiFe 2 O 4 nanoplates prepared with a Ni(NO 3 ) 2 /Fe(NO 3 ) 3 /KCl/NaCl molar ratio of 1:2:20:60. A high reversible capacity of 888 mAh g −1 is delivered over 100 cycles at a current density of 100 mA g −1 . Even at a current density of 5000 mA g −1 , the discharge capacity could still reach 173 mAh g −1 . Such excellent electrochemical performances of the NiFe 2 O 4 nanoplates are contributed to the short Li + diffusion distance of the nanosized building blocks and the synergetic effect of the Ni 2+ and Fe 3+ ions.