This study investigates the use of fluorine-modulated MXene-derived materials, specifically TiOF/Ti3C2, to enhance the performance of lithium-sulfur (Li-S) batteries. Fluorine modulation is achieved through a two-step hydrothermal method involving NH4F fluorination, which introduces fluorine atoms into the MXene structure. The resulting TiOF/Ti3C2 catalysts exhibit a unique three-dimensional structure and tailored F distribution. In situ characterizations and electrochemical analyses demonstrate that these catalysts effectively couple the multiphase sulfur conversion processes. The positive charge on Ti metal sites, increased due to the formation of O–Ti–F bonds, enhances the adsorption of polysulfides, provides more nucleation sites, and promotes the cleavage of S–S bonds, facilitating the deposition of Li2S at lower overpotentials. Additionally, fluorine captures electrons from Li2S dissolution due to charge compensation mechanisms, further improving the battery's performance. The study reveals that the theoretical basis of fluorine catalysis in Li-S batteries originates from Lewis acid-base mechanisms and charge compensation mechanisms. The findings highlight the potential of fluorine modulation in guiding the construction of fluorine-based catalysts and facilitating the integration of multiple consecutive heterogeneous catalytic processes in Li-S batteries.This study investigates the use of fluorine-modulated MXene-derived materials, specifically TiOF/Ti3C2, to enhance the performance of lithium-sulfur (Li-S) batteries. Fluorine modulation is achieved through a two-step hydrothermal method involving NH4F fluorination, which introduces fluorine atoms into the MXene structure. The resulting TiOF/Ti3C2 catalysts exhibit a unique three-dimensional structure and tailored F distribution. In situ characterizations and electrochemical analyses demonstrate that these catalysts effectively couple the multiphase sulfur conversion processes. The positive charge on Ti metal sites, increased due to the formation of O–Ti–F bonds, enhances the adsorption of polysulfides, provides more nucleation sites, and promotes the cleavage of S–S bonds, facilitating the deposition of Li2S at lower overpotentials. Additionally, fluorine captures electrons from Li2S dissolution due to charge compensation mechanisms, further improving the battery's performance. The study reveals that the theoretical basis of fluorine catalysis in Li-S batteries originates from Lewis acid-base mechanisms and charge compensation mechanisms. The findings highlight the potential of fluorine modulation in guiding the construction of fluorine-based catalysts and facilitating the integration of multiple consecutive heterogeneous catalytic processes in Li-S batteries.