Good electrical conductivity, strong catalytic activity, high interaction with lithium polysulfides (LIPSs), simple method, and low cost should be considered for the design and preparation of high-performance electrochemical catalysts that catalyze the conversion of LIPSs. In this work, we designed a bimetallic alloyed multifunctional interlayer with multiple adsorption/catalysis sites. The interwoven carbon fibers derived from bacterial cellulose (BC) not only contribute to reducing metal ions to metals but also confine the growth of Co–Fe alloys formed in situ. The metal supported on carbon is very effective for the conversion of LIPSs due to its high adsorption and catalytic sites. In addition, the synergistic effect between Fe and Co species leads to excellent bifunctional catalytic activity. Through detailed electrochemical analysis and theoretical calculations, we revealed that CoFe@CNFs has superior electrocatalytic activity, and the lithium–sulfur (Li–S) batteries with a catalytic interlayer can deliver satisfactory rate and cycle performance. At a high current density of 2C, the discharge capacity can still reach 627 mAh g^–1. At a current density of 1C, the Coulombic efficiency is maintained at a level close to 100% during the whole cycle process and a satisfying low capacity decay of 0.08% per cycle. More importantly, even if the ambient temperature drops to 0 °C, the Li–S battery using the interlayer can still be charged and discharged normally and shows acceptable discharge capacity, which shows that it has good rate kinetics.

中文翻译：

---

具有协同催化作用的 CoFe 合金装饰中间层改善多硫化物转化的电化学动力学

设计和制备催化 LIPSs 转化的高性能电化学催化剂应考虑导电性好、催化活性强、与多硫化锂 (LIPSs) 的相互作用高、方法简单、成本低等优点。在这项工作中，我们设计了一种具有多个吸附/催化位点的双金属合金多功能夹层。源自细菌纤维素 (BC) 的交织碳纤维不仅有助于将金属离子还原为金属，而且还限制了原位形成的 Co-Fe 合金的生长。由于其高吸附位点和催化位点，碳负载金属对于 LIPS 的转化非常有效。此外，Fe 和 Co 物种之间的协同作用导致优异的双功能催化活性。^–1。在1C的电流密度下，库仑效率在整个循环过程中保持在接近100%的水平，满足每次循环0.08%的低容量衰减。更重要的是，即使环境温度降至0°C，使用夹层的锂硫电池仍可正常充放电，并显示出可接受的放电容量，表明其具有良好的倍率动力学。