FeNb11O29 nanotubes: Superior electrochemical energy storage performance and operating mechanism

Due to high capacity from multiple redox couples, niobium-based oxides are promising anode materials for lithium-ion batteries (LIBs). However, their poor electronic conductivity restricts their electrochemical performance. Here, we report the FeNb 11 O 29 nanotubes as an advanced anode material. FeNb 11 O 29 nanotubes exhibit an impressive charge capacity of 272.64 mAh g −1 with high initial cycle Coulombic efficiency of 90.13% at 0.1 C and outstanding cyclic stability (only 0.0123% of capacity decay per cycle during 2000 cycles). Furthermore, according to the in-situ XRD , the behavior of lithium atoms distribution in the FeNb 11 O 29 framework during the insertion and extraction is studied in detail. In addition, full cells are assembled with commercially available cathodes. Coupled with LiFePO 4 , which is used as cathode, the full cell displays good electrochemical performance. In summary, FeNb 11 O 29 nanotubes can be used as an ideal anode material due to the excellent electrochemical performance.