“Rose Flowers” assembled from mesoporous NiFe₂O₄ nanosheets for energy storage devices

Rose flower-like NiFe₂O₄ composite, uniformly distributed on 3D Ni foam substrate, is successfully prepared via a facile, cost-effective hydrothermal growth process followed by sintering. The structure of the sample is tested by X-ray diffraction while the morphology is characterized by scanning electron microscopy and transmission electron microscopy. The flower-like NiFe₂O₄ materials are applied as potential anode for lithium-ion batteries (LIBs) which have the highest energy density and play enssential role for the electronic vehicles and sodium ion batteries (SIBs) which are candidates for replacing LIBs because of the abundant nature storage. Electrochemical results confirmed that the anode exhibits good cycling performance with a stable specific capacity and rate capability both in LIBs and SIBs. Furthermore, the cycling performance for LIBs is demonstrated to be 1126 mAh g⁻¹ even after 100 cycles while the Na storage behavior of rose flower-like NiFe₂O₄ materials as an anode material for SIBs is essentially investigated. It exhibits a high original discharge capacity of 584 mAh g⁻¹, and steady capacity retention of 304 mAh g⁻¹ after 100 cycles. Moreover, the long cycle capacity expressed to be ~250 mAh g⁻¹ even after 1300 cycles suggests a good cycling performance in this report for SIBs.