Preparation method of lithium-sulfur battery positive electrode material

The invention discloses a lithium-sulfur battery positive electrode material preparation method, which comprises: adding biomass macromolecules, TEMPO and NaBr into water, uniformly stirring, adding NaClO, dropwise adding NaOH to adjust the pH value to 7-14, carrying out a full reaction, adding NaBH4 for reduction, carrying out suction filtration after the reaction is completed, washing to a neutral state, adding into water, and dispersing to obtain an oxidized nanofiber dispersion solution (OCNF); mixing and stirring sulfonated carbon nanotubes and the oxidized nanofiber dispersion liquid, carrying out ultrasonic treatment, standing in a hydrochloric acid atmosphere for 12-48 hours, taking out formed gel, replacing the gel with an organic solvent, and carrying out freeze drying to obtain OCNF/CNT aerogel; placing in a tubular furnace, and carbonizing in an inert atmosphere to obtain CNF/CNT aerogel; the sublimed sulfur and the CNF/CNT aerogel are fully ground and mixed, the mixture is placed in an inert atmo