Pyrite as a Low-Cost Additive in Sulfur Cathode Material for Stable Cycle Performance

Various materials have been reported as an efficient host for sulfur to suppress large volume variation and polysulfide shuttle in lithium-sulfur batteries. Carbon materials are widely used as a matrix for sulfur to improve cycle performance and confine sulfur. Addition of transition metal sulfides into cathode material can improve cycle stability due to high efficiency of chemisorption and suppressing the polysulfide diffusion. In this work, various additions of pyrite to carbon and sulfur in the cathode material were investigated. The results show that the amount of pyrite has an affect on capacity and cycle stability of the electrode. Consequently, the lithium-sulfur batteries with the composite cathodes, containing 10 % of pyrite, exhibits stable discharge capacity of 788 mAh g-1 after 60 cycles at 0.2 C. Pyrite is a promising electrocatalyst in advanced lithium-sulfur batteries in the merits of low-cost, eco-friendliness and high activity towards polysulfides conversion reaction.