Hollow NiCo2O4 nanocages as sulfur host for advanced lithium-sulfur batteries

In this paper, hollow NiCo2O4 nanocages are prepared and designed as the sulfur host materials in the Li-S batteries. The as-prepared NiCo2O4/S composites have following advantages: (a) the hollow structure could buffer the volume change of the sulfur during the electrochemical reaction, (b) the NiCo2O4 could provide strong adsorption via chemical bond, which is beneficial for inhibiting the migration of the polysulfide between the cathode and anode. As a result, the NiCo2O4/S composites exhibit high specific capacity and stable cycle performance as the cathode materials for the Li-S batteries. The initial specific capacity of the NiCo2O4/S cathode is 1006 mAh g−1 at the current density of 0.2 C.