TiO2 nanotubes loaded WS2/MoS2 to construct heterostructures to accelerate the conversion of polysulfide in lithium-sulfur batteries

The introduction of heterostructures into the cathode materials of Li-S batteries can effectively anchor polysulfides, accelerate their redox reactions, and suppress the shuttle effect, thereby enhancing the sulfur utilization rate and the cycling stability of the battery. This work synthesized heterostructure materials TiO2 nanotubes loaded with WS2 and MoS2 via the hydrothermal method, forming heterostructure materials that enhance the catalytic conversion of LiPSs. Characterization results show that the tube-flower-like morphology and the tight interfacial connections between the components exhibit a strong adsorption capacity for LiPSs. These heterostructures accelerates the redox kinetics of the LiPSs transformation. Symmetrical cell tests further confirmed the bidirectional catalytic activity of WS2-TiO2 and MoS2-TiO2 for the rapid redox transformation of liquid-liquid conversion. The electrochemical test results indicate that the discharge-specific capacities of the S@WS2-TiO2 and S@MoS2-TiO2 cathodes were 1143.67 mAh g- 1 and 1086.2 mAh g- 1 at 0.1C, respectively, and 625.6 mAh g- 1 and 589.7 mAh g- 1 at 4C current density, demonstrating superior rate performance, high reversibility, and excellent cycling stability at high current densities. Introducing WS2 and MoS2 into TiO2 nanotubes to construct heterojunction materials provides a promising strategy for enhancing the performance of Li-S batteries.