Graphene-like porous carbon sheet/carbon nanotube composite as sulfur host for lithium-sulfur batteries

Abstract

In lithium-sulfur (Li–S) batteries, the shortened cycle life often arises from the migration of dissolved polysulfides to the anode. To address this issue, a sulfur host composite material was developed, featuring heteroatom-doped porous carbon combined with carbon nanotubes (PC/CNTs). The penetration of CNTs into the porous carbon imparts a cohesive high-conductivity network structure, thereby substantially augmenting the utilization of the active sulfur. Moreover, the copious pore architecture facilitates the diffusion of lithium ions and serves as sites for the physical adsorption of polysulfides. Furthermore, heteroatom doping can enhance the polarity of carbon materials, effectively quelling the “shuttle effect” by amplifying the chemical attraction and catalytic conversion of polysulfides. Drawing upon these findings, the S-PC/CNT electrode reveals stellar electrochemical performance.