A Universal Spinning-Coordinating Strategy to Construct Continuous Metal-Nitrogen-Carbon Heterointerface with Boosted Lithium Polysulfides Immobilization for 3D-Printed Li-S Batteries

Constructing intimate coupling between transition metal and carbon nanomaterials is an effective means to achieve strong immobilization of lithium polysulfides (LiPSs) in the applications of lithium-sulfur (Li-S) batteries. Herein, a universal spinning-coordinating strategy of constructing continuous metal-nitrogen-carbon (M-N-C, M = Co, Fe, Ni) heterointerface is reported to covalently bond metal nanoparticles with nitrogen-doped porous carbon fibers (denoted as M/M-N@NPCF). Guided by theoretical simulations, the Co/Co-N@NPCF hybrid is synthesized as a proof of concept and used as an efficient sulfur host material. The polarized Co-N-C bridging bonds can induce rapid electron transfer from Co nanoparticles to the NPCF skeleton, promoting the chemical anchoring of LiPSs to improve sulfur utilization. Hence, the as-assembled Li-S battery presents a remarkable capacity of 781 mAh g(-1) at 2.0 C and a prominent cycling lifespan with a low decay rate of only 0.032% per cycle. Additionally, a well-designed Co/Co-N@NPCF-S electrode with a high sulfur loading of 7.1 mg cm(-2) is further achieved by 3D printing technique, which demonstrates an excellent areal capacity of 6.4 mAh cm(-2) at 0.2 C under a lean-electrolyte condition. The acquired insights into strongly coupled continuous heterointerface in this work pave the way for rational designs of host materials in Li-S systems.

Automated summary

Constructing intimate coupling between transition metal and carbon nanomaterials is an effective means to achieve strong immobilization of lithium polysulfides in the applications of lithium-sulfur batteries. A universal spinning-coordinating strategy of constructing continuous metal-nitrogen-carbon heterointerface is reported and a proof of concept hybrid material is synthesized and used as an efficient sulfur host.