暨南大学李丹团队报道了以导电有机硫聚合物微笼为阴极的稳定Na/ K-S电池。相关研究成果发表在2024年12月17日出版的《美国化学会杂志》。

钠硫和钾硫电池具有高能量密度，与锂、钴和镍元素等稀有资源相比，使用天然更丰富、更实惠的金属，激发了强烈的研究兴趣。然而，用于Na/K储存的硫阴极受到可溶性多硫化物穿梭、较大体积变形，和缓慢氧化还原动力学的困扰。

该文中，研究人员报道了一种以微生物和元素硫为前体的，导电有机硫聚合物微胶囊可以有效地解决这些问题，以实现稳定的高容量钠硫和钾硫电池。共价键合的短链硫物种能够实现优异的反应动力学，并避免可溶性多硫化物的形成。具有内置腔的微胶囊架构缓冲了体积变形，以确保电极的弹性。

所得导电有机硫聚合物有望实现高容量和非凡的可循环性的结合，同时具有有前景的速率和库仑效率。特别是，作为K-S电池阴极，它可以提供1206.5 mAh g^–1的高容量，以及非凡的循环性能（1100次循环后容量保持率>99%），这比最先进的硫阴极要好得多。

该项工作设想了通过简单可行的方案，构建高性能导电有机硫阴极材料的新视角。

附：英文原文

Title: Stable Na/K–S Batteries with Conductive Organosulfur Polymer Microcages as Cathodes

Author: Xian Zeng, Zi-Jian Yi, Guo-Yu Zhu, Ning-Ning Zhu, Yan-Fei Chen, Ji-Miao Xiao, Run-Hang Chen, Menghua Yang, Hongchang Jin, De-Shan Bin, Dan Li

Issue&Volume: December 17, 2024

Abstract: Na–S and K–S batteries, with high-energy density, using naturally more abundant and affordable metals compared with rare resources like Li, Co, and Ni elements, have inspired intense research interest. However, the sulfur cathodes for Na/K storage are plagued by soluble polysulfide shuttling, larger volumetric deformation, and sluggish redox kinetics. Here, we report that a conductive organosulfur polymer microcage, fabricated facilely with the microbe and elemental sulfur as precursors, can effectively address these issues for stable high-capacity Na–S and K–S batteries. The covalently bonded short-chain sulfur species enable superior reaction kinetics and avoid soluble polysulfide formation. The microcage architecture with built-in cavities buffers the volume deformation to ensure a resilient electrode. The resultant conductive organosulfur polymer can promise a combination of high capacity and extraordinary cyclability with a promising rate and Coulombic efficiency. Especially, as a K–S battery cathode, it could deliver a high capacity of 1206.5 mAh g–1 together with an extraordinary cyclability (>99% capacity retention over 1100 cycles), which is much better than that of state-of-the-art sulfur cathodes. This work envisions new perspectives on building conductive organosulfur cathode materials with high performance via a simple and feasible protocol.

DOI: 10.1021/jacs.4c11845

Source: https://pubs.acs.org/doi/abs/10.1021/jacs.4c11845