Preparation of Highly Pyrrolic‐Nitrogen‐Doped Carbon Aerogels for Lithium‐Sulfur Batteries
Meng Zhang, Chunxiang Lu, Zhihong Bi, Xiaolu Xu, Xiaodan Ren, Xinzhi Li, Kuan Lu, Shuxia Yuan
Abstract
Abstract 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.