A facile route to prepare mixed transition metal oxide yolk-shell microspheres for enhanced lithium storage

A coordination co-precipitation route followed by a calcination process was developed to prepare mixed transition metal oxide microspheres with a yolk-shell structure. ZnCo2O4, NiCo2O4, MnCo2O4, ZnMn2O4 and CoMn2O4 have been successfully fabricated, which demonstrates the universality of this route. As a promising anode for lithium-ion batteries (LIBs), ZnCo2O4 was investigated as a typical example, which showed a remarkable reversible capacity of 1063 mA h g(-1) after 50 cycles at a current density of 200 mA g(-1) and a good rate capability of 839 mA h g(-1) after 200 cycles at a large current density of 900 mA g(-1). This work shows the extensive potential of a general route for the synthesis of yolk-shell microspheres for next-generation energy conversion and storage devices.