## 2 Results and Discussion
### Electrochemical Performance of MoS\({}_{2}\)-NG/PP Separator in Lithium-Sulfur Batteries  
To demonstrate the enhancement of the overall electrochemical performance of lithium-sulfur batteries, MoS\({}_{2}\)-NG/PP separators were used to assemble coin cells, which were then subjected to cyclic voltammetry (CV), long-cycle charge/discharge, and rate performance tests. Figure 5a shows the CV curves of cells assembled with MoS\({}_{2}\)/PP, MoS\({}_{2}\)-G/PP, and MoS\({}_{2}\)-NG/PP separators within a voltage range of 1.7-2.8 V. Two distinct reduction peaks appear at approximately 2.3 V and 2.0 V, corresponding to the reduction of solid S\({}_{8}\) to soluble polysulfides and their further reduction to the final solid product Li\({}_{2}\)S, respectively. The two oxidation peaks correspond to the re-oxidation of Li\({}_{2}\)S into polysulfides and further oxidation to S\({}_{8}\). Comparing the cathodic scan curves of the three separators, the first reduction peak of MoS\({}_{2}\)-G/PP and MoS\({}_{2}\)-NG/PP shows a similar peak current and position, while MoS\({}_{2}\)/PP exhibits a more delayed peak with a lower peak current. Although the second reduction peak positions are close for all three separators, MoS\({}_{2}\)-NG/PP exhibits the highest current response, indicating a superior catalytic effect of MoS\({}_{2}\)-NG in facilitating the conversion of polysulfides to Li\({}_{2}\)S, consistent with the previous Li\({}_{2}\)S deposition experiments. During the anodic scan, MoS\({}_{2}\)-NG also demonstrates the highest peak current, suggesting that it optimizes the redox reaction kinetics within the battery system. Figure 5b displays the constant current charge/discharge curves of cells with MoS\({}_{2}\)/PP, MoS\({}_{2}\)-G/PP, and MoS\({}_{2}\)-NG/PP separators at 0.2 C. The discharge process shows two distinct voltage plateaus: the first plateau around 2.35 V corresponds to the ring-opening reaction of S\({}_{8}\) converting to polysulfides, and the second plateau around 2.1 V corresponds to the further conversion of polysulfides to Li\({}_{2}\)S, theoretically contributing 75% of the total discharge capacity. The charge curve indicates the dissolution and conversion of Li\({}_{2}\)S back into polysulfides and their re-oxidation to S\({}_{8}\). After the first discharge plateau, the specific capacities of MoS\({}_{2}\)/PP, MoS\({}_{2}\)-G/PP, and MoS\({}_{2}\)-NG/PP separators differ only slightly, all around 380 mAh g\({}^{-1}\). However, during the second discharge stage, corresponding to the conversion of polysulfides to Li\({}_{2}\)S, MoS\({}_{2}\)-NG/PP exhibits a longer second discharge plateau, releasing a more specific capacity. This is attributed to its strong catalytic effect, which effectively induces the nucleation and growth of Li\({}_{2}\)S, thereby releasing more capacity in this stage. Figure 5c presents the rate performance of cells with the three different separators, with charge/discharge rates ranging from 0.2 C to 3 C and finally back to 0.2 C. The cell with the MoS2-NG/PP separator delivers specific capacities of 1269, 1047, 918, 798, and 714 mAh g\({}^{-1}\) at 0.2, 0.5, 1, 2, and 3 C, respectively. When the rate returns to 0.5 and 0.2 C, the specific capacities recover to 1004 and 1117 mAh g\({}^{-1}\), respectively. In contrast, due to the relatively poor chemical adsorption and catalytic performance of MoS2 and MoS2-G towards polysulfides, the discharge capacities of cells with MoS2/PP and MoS2-G/PP separators are consistently lower than those with MoS2-NG/PP separators at various current densities. When compared to other MoS2-based materials reported in the literature [30; 36; 37; 38], MoS2-NG exhibits significantly higher rate performance and specific capacities. This demonstrates that MoS2-NG has excellent catalytic activity, effectively suppressing the shuttle effect of polysulfides and inducing the nucleation and growth of Li2S, thereby enhancing the rate performance of the battery.