Sandwich Structures Constructed by ZnSe⊂N-C@MoSe2Located in Graphene for Efficient Sodium Storage

Hybrid hierarchical micro/nanostructures possess great potential in engineering of advanced electrode materials for sodium-ion batteries (SIBs). Herein, a sandwich hierarchical architecture composed of ZnSe nanoparticles fastened in N-doped carbon polyhedra anchoring onto graphene with the modification of MoSe(2)nanosheets (ZnSe subset of N-C@MoSe2/rGO) is synthesized by a self-template and subsequent selenization strategy. Due to the distinctive architectural and multicompositional features, these hybrids deliver a high reversible capacity of 319.4 mAh g(-1)at 1 A g(-1)for 1800 cycles, 206.5 mA h g(-1)at 6 A g(-1)for 2800 cycles, and 177.7 mAh g(-1)at 10 A g(-1)for 5000 cycles, as well as a better rate capability up to 10 A g(-1)with a reversible capacity of 224.4 mAh g(-1)as an anode material for SIBs. By comparing the capacity contribution, electrochemical impedance spectra andD(Na+)of different materials, the advantages of ZnSe subset of N-C@MoSe2/rGO are confirmed. The sodium storage mechanism of hybrids is further revealed by in situ X-ray diffraction patterns and high-resolution transmission electron microscopy results. The improved sodium storage properties of hybrids manifest the significance of elaborate construction of novel multicomponent hierarchical architectures with higher complexity.