The Effective Design of a Polysulfide-Trapped Separator at the Molecular Level for High Energy Density Li-S Batteries.

摘要: In this work, the lightweight and scalable organic macromolecule graphitic carbon nitride (g-C3N4) with enriched polysulfide adsorption sites of pyridinic-N was introduced to achieve effective functionalization separator at molecular level. This simple method overcomes difficulty low doping content as well existence an uncontrolled form nitrogen heteroatom in final product. Besides conventional pyridinic–N-Li bond formed vacancies g-C3N4, C–S interestingly observed between g-C3N4 Li2S, which endowed inherent capacity for polysulfides. addition, microsized provided coating layer good mechanical strength guarantee its restriction function polysulfides during long cycling. As a result, excellent reversible 840 mA h g–1 retained 0.5 C after 400 cycles pure sulfur electrode, much better than that cell innocent carbon-coated separator. Even cur...