Fe_2VO_4 Nanoparticles Anchored on Ordered Mesoporous Carbon with Pseudocapacitive Behaviors for Efficient Sodium Storage

摘要

Iron vanadates are attractive anode materials for sodium-ion batteries (SIBs) because of their abundant resource reserves and high capacities. However, their practical application is restricted by the aggregation of materials, sluggish reaction kinetics, and inferior reversibility. Herein, Fe2VO4 nanoparticles are anchored on the ordered mesoporous carbon (CMK-3) nanorods to assemble 3D Fe2VO4@CMK-3 composites, by solvothermal treatment and subsequent calcination. The resulting composites provide abundant active sites, high electrical conductivity, and excellent structural integrity. The pseudocapacitive-controlled behavior is the dominating sodium storage mechanism, which facilitates a fast charge/discharge process. The Fe2VO4@CMK-3 composites exhibit stable sodium-ion storage (219 mAh g(-1) under 100 mA g(-1) after 300 cycles), good rate performance (144 mAh g(-1) at 3.2 A g(-1)), and excellent cycling performance (132 mAh g(-1) at 1 A g(-1) with capacity retention of 96.4% after 800 cycles). When coupled with a NaNi1/3Fe1/3Mn1/3O2 cathode, the sodium-ion full cell displays excellent cycling stability (94 mAh g(-1) after 500 cycles at 500 mA g(-1)). These findings point to the potential of Fe2VO4@CMK-3 for application as anodes in SIBs.