In situ growth C/MnO2 composites as sulfur host for lithium-sulfur batteries with superior electrochemical behaviors

Abstract

To suppress the shuttle effect of polysulfide in lithium-sulfur batteries, the design of sulfur hosts with physical and chemical adsorption ability has become a hot research topic. In this paper, we propose a strategy to develop carbon/MnO₂ composites as sulfur host in lithium-sulfur batteries. The MnO₂ particles are in situ grown on the surface of the carbon materials. On the one hand, the carbon could provide physical adsorption for polysulfide and improve the electronic conductivity. On the other hand, the metal oxide MnO₂ can provide strong chemical adsorption during the electrochemical cycles. As a result, the as-prepared C/MnO₂@S composites exhibit high capacity and stable cycling performance. After 300 cycles, the discharge specific capacity of C/MnO₂@S cathode is 752 mAh g⁻¹ at high rate of 2 C.