Yolk@Shell or Concave Cubic NiO-Co₃O₄@C Nanocomposites Derived from Metal-Organic Frameworks for Advanced Lithium-Ion...

Novel hybrid metal oxides with advanced architectures are extensively pursued to achieve synergetic properties with respect to improved lithium-ion storage properties. Here, rationally designed yolk@shell or concave NiO-Co₃O₄@C (YNCC or CNCC) nanocubes have been fabricated by the simple and versatile thermolysis-induced transformation of metal-organic frameworks (MOFs), aimed at simultaneously addressing the capacity fade and conductivity deficiency of metal oxides. The as-prepared nanocomposites with plentiful hierarchical pores integrate the distinct functionalities of the ternary components: NiO and Co₃O₄ as the major active materials can guarantee high capacity, while carbon can improve the conductivity and accommodate volume changes. Benefitting from the intrinsic material and architecture features, the YNCC and CNCC nanocomposites deliver excellent electrochemical performances with high reversible specific capacity, superior cycling stability (803 and 870 mAh g^-1 at 100 mA g^-1 after 100 cycles), and good rate capability (339 and 398 mAh g^-1 at 2 A g^-1) as anode materials for lithium-ion batteries.