Sulfur/Co₃O₄ nanotube composite with high performances as cathode materials for lithium sulfur batteries

To improve the overall electrochemical performance of the sulfur cathode in Li / S batteries, a hollow Co 3 O 4 nanotube with a channel measuring approximately 12.5 nm in diameter is synthesized and then impregnated with sulfur via a melt-diffusion strategy. X-ray powder diffraction (XRD), transmission electron microscopy (TEM), Brunauer–Emmett–Teller (BET) analysis and thermogravimetric analysis indicate that sulfur impregnated the channels of the hollow Co 3 O 4 nanotube. Because the sulfur is mostly restricted to the Co 3 O 4 nanotubes, a sulfur/ Co 3 O 4 cathode with 10 wt.% sulfur loading delivers an initial discharge capacity of 963.4 mAh g -1 , with much of the capacity contributed by Co 3 O 4 , and exhibits excellent reversibility with a capacity reservation of 80.8% after 100 cycles.