Molybdenum nitride/N-doped carbon nanospheres for lithium-O₂ battery cathode electrocatalyst.

Molybdenum nitride/N-doped carbon nanospheres (MoN/N-C) are synthesized by hydrothermal method followed by ammonia annealing. The as-prepared MoN/N-C nanospheres manifest considerable electrocatalytic activity toward oxygen reduction reaction in nonaqueous electrolytes because of its nanostructure and the synergetic effect between MoN and N-C. Furthermore, the MoN/N-C nanospheres are explored as cathode catalyst for Li-O2 batteries with tetra-(ethylene glycol) dimethyl ether as the electrolyte. The assembled batteries deliver alleviated overpotentials and improved battery lifespan, and their excellent performances should be attributed to the unique hierarchical structure and high fraction of surface active sites of cathode catalyst.