The study investigates the enhancement of sulfur reduction kinetics in lithium-sulfur (Li-S) batteries using an Mo-based MXene heterostructure (MoS2@Mo2C). The MoS2@Mo2C heterojunction is synthesized by partially vulcanizing Mo2C MXene with sulfur, creating an electron delocalization effect. This effect promotes ion desolvation, increases the number of free lithium ions (Li+), and accelerates Li+ transport, thereby improving polysulfide conversion efficiency. The material also enhances the oxidation and reduction of polysulfides through its defects and vacancies, further boosting catalytic efficiency. Electrochemical tests show that the Li-S battery with the MoS2@Mo2C electrocatalyst maintains high capacity and rate performance over 500 cycles at 1 C, with an ideal capacity of 664.7 mAh·g-1. The battery retains 775.6 mAh·g-1 after 100 cycles under high loading conditions and 838.4 mAh·g-1 after 70 cycles at 0 °C, demonstrating excellent stability and low decay rate (0.063%). These results highlight the effectiveness of delocalized electrons in accelerating the catalytic conversion of lithium polysulfides, making the MoS2@Mo2C material a promising candidate for enhancing Li-S battery performance.The study investigates the enhancement of sulfur reduction kinetics in lithium-sulfur (Li-S) batteries using an Mo-based MXene heterostructure (MoS2@Mo2C). The MoS2@Mo2C heterojunction is synthesized by partially vulcanizing Mo2C MXene with sulfur, creating an electron delocalization effect. This effect promotes ion desolvation, increases the number of free lithium ions (Li+), and accelerates Li+ transport, thereby improving polysulfide conversion efficiency. The material also enhances the oxidation and reduction of polysulfides through its defects and vacancies, further boosting catalytic efficiency. Electrochemical tests show that the Li-S battery with the MoS2@Mo2C electrocatalyst maintains high capacity and rate performance over 500 cycles at 1 C, with an ideal capacity of 664.7 mAh·g-1. The battery retains 775.6 mAh·g-1 after 100 cycles under high loading conditions and 838.4 mAh·g-1 after 70 cycles at 0 °C, demonstrating excellent stability and low decay rate (0.063%). These results highlight the effectiveness of delocalized electrons in accelerating the catalytic conversion of lithium polysulfides, making the MoS2@Mo2C material a promising candidate for enhancing Li-S battery performance.