Prussian Blue: A Potential Material to Improve the Electrochemical Performance of Lithium-Sulfur Batteries

The Prussian blue, as a potential adsorbent of polysulfides to suppress the dissolution and shuttle of polysulfides for lithium-sulfur batteries, has been studied in this work. Our results show that Prussian blue improves the electrochemical reaction kinetics during discharge/charge processes. More importantly, the cathode with Prussian blue exhibits better cycling stability and higher discharge capacity retention (722 mAh g^-1 at 0.2 A g^-1 after 100 cycles) than the one without Prussian blue (151 mAh g^-1). These improvements of electrochemical performances are ascribed to the fact that Prussian blue is very effective in suppressing the dissolution of polysulfides into liquid electrolyte by chemical adsorption.