TiO2@C@MoS2 Spheres as Efficient Sulfur Host for Lithium-Sulfur Batteries

In this paper, TiO2 @ C @ MoS2 composite has been successfully synthesized by wrapping TiO2 spheres with C layer and MoS2 nanosheets. Firstly, TiO2 spheres are synthesized by solvothermal and subsequent calcination process; subsequently, TiO2 spheres are coated with dopamine and carbonized to form TiO2@C spheres; then, ultrathin MoS2 nanosheets grew outside the TiO2@C spheres; finally, sulfur infiltrated into the TiO2@C@MoS2 spheres by melt diffusion method and the TiO2@C@MoS2/S spheres were successfully synthesized for the sulfur main body of lithium-sulfur batteries. The composite material has strong binding for polysulfides and good adsorption and catalysis, so it is an ideal carrier for sulfur host materials. By using such a composite material as a positive electrode in a Li-S battery, better electrochemical performance has been achieved. The results show that, the sulfur loading is about 63%, and the specific capacity of the sulfur positive electrode reaches 535.9 mAh g(-1) after 99 cycles at 0.1 C current density, and the specific capacity reaches 392.4 mAh g(-1) after 100 cycles at 0.5 C current density. The capacity retention rate is about 76.28%.