Wu Qingping, Chen Keyi, Shadike Zulipiya, Li Chilin
Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, P. R. China.
State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai 201899, P. R. China.
ACS Nano. 2024 May 28;18(21):13468-13483. doi: 10.1021/acsnano.3c09919. Epub 2024 May 13.
An environmental-friendly and sustainable carbon-based host is one of the most competitive strategies for achieving high loading and practicality of Li-S batteries. However, the polysulfide conversion reaction kinetics is still limited by the nonuniform or monofunctional catalyst configuration in the carbon host. In this work, we propose a catalysis mode based on "relay-type" co-operation by adjacent dual-metal single atoms for high-rate and durable Li-S batteries. A discarded sericin fabric-derived porous N-doped carbon with a stacked schistose structure is prepared as the high-loading sulfur (84 wt %) host by a facile ionothermal method, which further enables the uniform anchoring of Fe/Co dual-metal single atoms. This multifunctional host enables superior lithiophilic-sulfiphilic and electrocatalytic capabilities contributed by the "relay-type" single-atom modulation effects on different conversion stages of liquid polysulfides and solid LiS/LiS, leading to the suppression of the "shuttle effect", alleviation of nucleation and decomposition barriers of LiS, and acceleration of polysulfide conversion kinetics. The corresponding Li-S batteries exhibit a high specific capacity of 1399.0 mA h g, high-rate performance up to 10 C, and excellent cycling stability over 1000 cycles. They can also endure the high sulfur loading of 8.5 mg cm and the lean electrolyte condition and yield an areal capacity as high as 8.6 mA h cm. This work evidentially demonstrates the potential of waste biomass reutilization coupled with the design of a single-atom system for practical Li-S batteries with high energy density.
一种环境友好且可持续的碳基主体材料是实现锂硫电池高负载量和实用性的最具竞争力策略之一。然而，多硫化物转化反应动力学仍然受到碳基主体中不均匀或单功能催化剂构型的限制。在这项工作中，我们提出了一种基于相邻双金属单原子“接力型”合作的催化模式，用于高倍率和耐用的锂硫电池。通过简便的离子热法制备了一种具有堆叠片状结构的废弃丝胶织物衍生多孔氮掺杂碳，作为高负载硫（84 wt%）主体材料，这进一步实现了铁/钴双金属单原子的均匀锚定。这种多功能主体材料通过对液态多硫化物和固态Li₂S/Li₂S₂不同转化阶段的“接力型”单原子调制效应，实现了卓越的亲锂-亲硫和电催化能力，从而抑制了“穿梭效应”，减轻了Li₂S的成核和分解障碍，并加速了多硫化物转化动力学。相应的锂硫电池表现出1399.0 mA h g的高比容量、高达10 C的高倍率性能以及超过1000次循环的优异循环稳定性。它们还能承受8.5 mg cm⁻²的高硫负载和贫电解质条件，并产生高达8.6 mA h cm⁻²的面积容量。这项工作有力地证明了废弃生物质再利用与单原子体系设计相结合对于具有高能量密度的实用锂硫电池的潜力。
