Surface Functionalization of Carbon Architecture with Nano-MnO2 for Effective Polysulfide Confinement in Lithium-Sulfur Batteries.

Li-S batteries have received tremendous attention owing to their high theoretical capacity (1672 mA h g-1 ), sulfur abundance, and low cost. However, main systemic issues, associated with polysulfide shuttling and low Coulombic efficiency, hinder the practical use of the sulfur electrode in commercial batteries. Herein, we demonstrate an effective strategy of decorating nano-MnO2 (less than 10 wt %) onto the sulfur reservoir to capture the out-diffused polysulfides through chemical interaction and thereby improve the electrochemical performance of the sulfur electrode without increasing the mass burden of total battery configuration. Pistachio shell-derived sustainable carbon (PC) was employed as effective sulfur containers owing to its structural characteristics (interconnected macro channels and micropores). With the aids of the structural benefits of the PC scaffold and the uniform decoration of nano-MnO2 , polysulfide shuttling was significantly suppressed and the cycling performance of the sulfur cathode was dramatically improved over 250 cycles.