Ammonia-Treated Ordered Mesoporous Carbons with Hierarchical Porosity and Nitrogen-Doping for Lithium-Sulfur Batteries

摘要

Developed porosity and high-level heteroatom-doping are necessary to acquire the advanced carbon materials as sulfur hosts for lithium-sulfur batteries with high sulfur loading. We herein demonstrated that hierarchical ordered micro/mesoporous carbons with controllable porosity and nitrogen functionality could be prepared via two scalable steps which are based on aqueous self-assembly and ammonia activation processes. The effects of porosity and nitrogen doping upon the electrochemical performances of the carbon/sulfur hybrids as the cathodes in lithium-sulfur batteries were investigated. It demonstrated that the carbon materials with balanced porosity and nitrogen-doping level could effectively increase the conductivity of sulfur and alleviate the “shuttle effect” and exhibit high specific capacity, good rate performance, and superior cycling stability.