An Environmental-Friendly and Sustainable Ramie-Derived Co/N-Doped Carbon With Dual Function for Synergistic Polysulfide Regulation in Li-S Batteries

en The dual challenges of environmental sustainability and rising energy needs underscore the necessity for high-energy-density batteries, making lithium–sulfur (LSB) systems with their high theoretical capacity highly attractive. However, the polysulfide shuttle, coupled with inherent kinetic limitations in the sulfur reduction reaction, significantly compromises the battery's commercialization. Utilizing biomass-derived materials presents a sustainable and cost-effective approach to mitigating these issues. Therefore, in this study, a series of cobalt–nitrogen co-doped porous carbon materials (Co,N-C) were prepared from ramie waste glue by adjusting the cobalt source content, and their electrochemical properties as sulfur hosts were systematically investigated. Among them, Co,N-C-2 exhibits the best performance. The three-dimensional (3D) porous architecture promotes electrolyte penetration and lithium–ion mobility, whereas the Co,N co-doping sites effectively adsorb lithium polysulfides, markedly reducing the shuttle effect and improving conversion kinetics. The Co,N-C-2/S cathode has an initial discharge capacity of 1274.2 mAh g −1 at 0.2C and sustains a reversible capacity of 540.6 mAh g −1 after 350 cycles at 1C, demonstrating a minimal degradation rate of 0.11% each cycle. This study offers a sustainable and cost-effective design strategy for high-performance LSBs. 摘要 zh 环境可持续性和不断增长的能源需求所带来的双重挑战凸显了高能量密度电池的必要性,这使得具有高理论容量的锂硫(LSB)电池系统极具吸引力。然而,多硫化物穿梭效应以及硫还原反应固有的动力学限制严重阻碍了该电池的商业化进程。利用生物质衍生材料为解决这些问题提供了一种可持续且经济有效的途径。因此,在本研究中,通过调整钴源含量,以苎麻废胶为原料制备了一系列钴氮共掺杂多孔碳材料(Co,N–C),并对其作为硫宿主的电化学性能进行了系统研究。其中,Co,N-C-2 表现最佳。三维(3D)多孔结构促进了电解质的渗透和锂离子的迁移,而钴氮共掺杂位点能有效吸附多硫化锂,显著减少了穿梭效应并改善了转化动力学。Co,N-C-2/S 正极在 0.2C 时的初始放电容量为 1274.2 mAh g −1 ,在 1C 下经过 350 次循环后仍能保持 540.6 mAh g −1 的可逆容量,每循环的容量衰减率仅为 0.11%。这项研究为高性能锂硫电池提供了一种可持续且经济的设计策略。