Constructing Multifunctional Heterostructure of Fe2O3@Ni3Se4 Nanotubes

Abstract Heterostructures have attracted increasing attention due to their amazing synergetic effects, which may improve the electrochemical properties, such as good electrical/ionic conductivity, electrochemical activity, and mechanical stability. Herein, novel hierarchical Fe 2 O 3 @Ni 3 Se 4 nanotubes are successfully fabricated by a multistep strategy. The nanotubes show length sizes of ≈250–500 nm, diameter sizes of ≈100–150 nm, and wall thicknesses of ≈10 nm. The as‐prepared Fe 2 O 3 @Ni 3 Se 4 nanotubes with I Ni:Fe = 1:10 show excellent Li storage properties (897 mAh g −1 high reversible charge capacity at 0.1 A g −1 ), good rate performance (440 mAh g −1 at 5 A g −1 ), and outstanding long‐term cycling performance (440 mAh g −1 at 5 A g −1 during the 300th cycle) as an anode material for lithium ion batteries. In addition, the Fe 2 O 3 @Ni 3 Se 4 nanotubes with I Ni:Fe = 1:10 (the atomic ratio between Ni and Fe) show superior electrocatalytic performance toward the oxygen evolution reaction with an overpotential of only 246 mV at 10 mA cm −2 and a low Tafel slope of 51 mV dec −1 in 1 m KOH solution.