Electrocatalysis of Ruthenium Nanoparticles-Decorated Hollow Carbon Spheres for the Conversion of Li₂S₂/Li₂S in Lithium–Sulfur Batteries

Controlling “polysulfide dissolution” and pacifying “polysulfide shuttle” hold the key in developing a lithium–sulfur battery with superior electrochemical performance. Further, exploration of the concept of electrocatalysts plays a significant role in enhancing the electrochemical reversibility of polysulfides in lithium–sulfur battery. Herein, ruthenium nanoparticles-decorated porous, hollow carbon spheres have been successfully prepared and deployed as electrocatalyst as well as sulfur host in the lithium–sulfur battery assembly. Interaction of sulfur with ruthenium nanoparticles has been explained with appropriate electroanalytical and electrochemical characterization techniques. We observe that lithium–sulfur battery containing C–Ru–S cathode with a fixed sulfur loading exhibits a significantly improved capacity of 1200 mA h g–1 at C/10 current rate for 100 cycles. Volume expansion-related issues are found to get addressed by the hollow structured carbon spheres, and the electrocatalytic activity will improve the reaction kinetics of the conversion of Li2S2 to Li2S and vice versa.