Polar, catalytic, and conductive CoSe2/C frameworks for performance enhanced S cathode in Li-S batteries

Abstract Lithium-sulfur battery (Li-S) is considered as one of the new-generation rechargeable batteries with high performance because of its extremely high theoretical capacity, energy density, environmental harmony and low cost. However, low electrical and ionic conductivity of sulfur, safety concerns and parasitic reaction generated by the dissolved polysulfide species in electrolyte hinder the commercialization of Li-S battery. Herein, we report a polyhedral porous structure comprising of carbon coating metal selenide nanoparticles (CoSe2/C), which could not only host sulfur for Li-S battery owing to its porous and conductive structure, but also mitigate the shuttle phenomenon by polysulfides adsorption and catalytic acceleration of redox kinetics. As a result, a performance enhanced CoSe2/C-S electrode for Li-S battery is achieved.