Carbon-based cathode host derived from crosslinked porous polyimides for lithium-sulfur batteries and their electrochemical properties

Carbon-based porous materials as Li-S batteries cathode hosts have received widespread attention because of the superiority of fine physical confinement, vast accommodation voids and excellent conductive networks, towards realizing the adsorption-diffusionconversion of lithium polysulfides (LiPSs). However, carbon-based materials are usually non-polar, which can only act as physical barriers to limit polysulfides shuttle behavior during short-term cycling of Li-S batteries, lacking strong chemical entrapment towards the polar polysulfides. Herein, we successfully synthesize two novel carbon-based hierarchical porous materials (CR-PPIs@800) derived from crosslinked porous polyimides (CRPPIs) via traditional polymerization and crosslinking reaction as well as high-temperature treatment. Because the pre-designed porous architectures, CR-PPIs@800 not only give hierarchical porous structure for accommodating LiPSs, but also afford strong chemisorption interaction from high heteroatom N species for adsorbing LiPSs and buffering shuttle behaviors. The carbon networks of CR-PPIs@800 possess valid ion storage and transportation network for accelerating charge/ion migration of LiPSs. Profiting from above advantages, S/CR-PPIs@800 composites cathodes realize the fast conversion of LiPSs, and show promoted electrochemical properties. (c) 2022 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.