Designed formation of Co 3 O 4 @NiCo 2 O 4 sheets-in-cage nanostructure as high-performance anode material for lithium-ion batteries.

Structural and compositional control of functional nanoparticles is considered to be an efficient way to obtain enhanced chemical and physical properties. A unique Co 3 O 4 @NiCo 2 O 4 sheets-in-cage nanostructure is fabricated via a facile conversion reaction, involving subsequent hydrolysis and annealing treatment. Such hollow nanoparticles provide an excellent property for Li storage.