Preparation of Highly Pyrrolic-Nitrogen-Doped Carbon Aerogels for Lithium-Sulfur Batteries

A cellulose-based, highly pyrrolic-nitrogen-doped carbon aerogel (PNCA) was successfully prepared by using a facile and ecofriendly in situ dissolution process; the resulting aerogel had a honeycomb-like three-dimensional structure and a highly pyrrole-nitrogen-doped configuration. As the host material of the cathode in lithium-sulfur batteries, PNCA achieved a high sulfur loading up to 76.7 %, owing to the distribution of pyrrole nitrogen and the three-dimensional network structure. As a consequence, this composite cathode exhibits outstanding electrochemical performance, including long-term cycling stability (1292.8 mA h g(-1) at 0.2 C over 500 cycles and 540.5 mA h g(-1) at 1 C over 1000cycles) and excellent rate performance (1249.9 mA h g(-1) at 0.2 C, 1060 mA h g(-1) at 0.5 C, 936.3 mA h g(-1) at 1 C, and 698 mA h g(-1) at 3 C remained). This study aims at providing new insights for the synthesis of highly reactive nitrogen-doped carbon materials and then further proposing a future viewpoint on the design and development of advanced host materials for lithium-sulfur batteries. Furthermore, the key mechanism of the pyrrole-doped nitrogen configuration in the catalytic conversion of polysulfides was revealed for the first time after being combined with DFT theoretical calculations.

Automated summary

PNCA, a cellulose-based highly pyrrolic-nitrogen-doped carbon aerogel, exhibits excellent electrochemical performance as a cathode material in lithium-sulfur batteries. The study sheds light on the potential and future applications of nitrogen-doped carbon materials in lithium-sulfur batteries.