Synthesis of sulfur/FePO₄/graphene oxide nanocomposites for lithium-sulfur batteries

Sulfur/FePO₄/graphene oxide (SFGO) nanocomposites were fabricated. The electrochemical measurements show that SFGO nanocomposites deliver a high initial discharge capacity of 1337.8 mAh g^-1 at 1 C. After 100 cycles, SFGO nanocomposites still remain a discharge capacity of 608.9 mAh g^-1, the coulombic efficiency is 94%. Herein, as an anchoring materials, FePO₄ not only suppresses the dissolution of lithium polysulfides, but also facilitates the transfer of Li⁺ ions and electrons. In addition, as a dispersant in the nanocomposites, FePO₄ is more advantageous for limiting the agglomeration of sulfur nanoparticles. The graphene oxide (GO) wraps on the outside of the composites to accommodate lithium polysulfides as well as volume expansion of the electrode during cycle process. The excellent electrochemical performance and special structure of the nanocomposites open a new window to design novel S-based electrodes.