Carbon doping endows silicon oxide with enhanced redox kinetics of polysulfides

Abstract

Carbon-doped SiO₂ is synthesized by the in situ carbonization of halloysite. Carbon atoms partially substitute O atoms to form Si–C bonds and manipulate the localized electronic states of Si atoms, thereby endowing SiO₂ with suitable adsorption strength and reducing the activation energy barrier for polysulfides in the sulfur redox. The C–SiO₂/S cathodes for Li–S batteries exhibited superior electrochemical performance.