Electrocatalyzing S Cathodes <i>via</i> Multisulfiphilic Sites for Superior Room-Temperature Sodium–Sulfur Batteries
Hanwen Liu, Wei Pei, Wei‐Hong Lai, Zichao Yan, Huiling Yang, Yaojie Lei, Yunxiao Wang, Qinfen Gu, Si Zhou, Shulei Chou, Huan Liu, Shi Xue Dou
Abstract
Room-temperature sodium–sulfur (RT-Na/S) batteries hold great promise for sustainable and cost-effective applications. Nevertheless, it remains a great challenge to achieve high capacity and cycling stability due to the low activity of sulfur and the sluggish conversion kinetics between polysulfide intermediates and sodium sulfide. Herein, an electrocatalyzing S cathode is fabricated, which consists of porous core–shell structure and multisulfiphilic sites. The flexible carbon structure effectively buffers volume changes during cycling and provides enclosed spaces to store S 8 with exceptional conductivity. Significantly, the multisulfiphilic sites (ZnS and CoS 2 ) enhance catalysis toward multistep S conversion, which effectively suppresses long-chain polysulfides dissolution and improves the kinetics of short-chain polysulfides. Thus, the obtained S cathodes achieve an enhanced cycling performance (570 mAh g –1 at 0.2 A g –1 over 1000 cycles), decent rate capability (250 mAh g –1 at 1.0 A g –1 over 2000 cycles), and high energy density of 384 Wh kg –1 toward practical applications.