Hierarchical N-Doped HMCN/CNT Hybrid Carbon Frameworks Assembling Cobalt Selenide Nanoparticles for Advanced Properties of Lithium/Sodium Storage

A hybrid nanostructure with Co 0.85 Se nanoparticles anchored in nitrogen-doped hollow mesoporous carbon nanospheres/carbon nanotubes (Co 0.85 Se/N-HMCNs/CNTs) is elaborately fabricated by a pyrolysis–reduction–selenization strategy derived from yolk–shell zeolitic imidazolate framework-67 (ZIF-67)@HMCNs, which are synthesized by the confined growth of ZIF-67 inside HMCNs regarded as nanoreactors. Benefitting from the robust hollow carbon frameworks made of nitrogen-doped hollow mesoporous carbon nanospheres, carbon nanotubes, and highly active Co 0.85 Se ultrafine nanoparticles, the as-prepared nanocomposites show greatly enhanced lithium/sodium storage properties. When the Co 0.85 Se/N-HMCNs/CNTs are applied to lithium-ion batteries as anode materials, the advanced nanocomposite delivers excellent cycling stability (286 and 153 mA h g −1 at 10 A g −1 after 5000 and 10 000 cycles) and high rate performance (501 mA h g −1 at 5 A g −1 ). When the Co 0.85 Se/N-HMCNs/CNTs are applied to sodium-ion batteries as anode materials, the material realizes better cycling performance (102 mA h g −1 at 1 A g −1 after 1000 cycles) and excellent rate performance (132 mA h g −1 at 5 A g −1 ).