Fan Shuang, Huang Shaozhuan, Pam Mei Er, Chen Song, Wu Qingyun, Hu Junping, Wang Ye, Ang Lay Kee, Yan Congcong, Shi Yumeng, Yang Hui Ying
International Collaborative Laboratory of 2D Materials for Optoelectronics Science and Technology of Ministry of Education, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, 518060, China.
Pillar of Engineering Product Development, Singapore University of Technology and Design, 8 Somapah Road, Singapore, 487372, Singapore.
Small. 2019 Dec;15(51):e1906132. doi: 10.1002/smll.201906132. Epub 2019 Nov 22.
The polysulfide shuttle effect and sluggish reaction kinetics hamper the practical applications of lithium-sulfur (Li-S) batteries. Incorporating a functional interlayer to trapping and binding polysulfides has been found effective to block polysulfide migration. Furthermore, surface chemistry at soluble polysulfides/electrolyte interface is a crucial step for Li-S battery in which stable cycling depends on adsorption and reutilization of blocked polysulfides in the electrolyte. A multifunctional catalytic interface composed of niobium nitride/N-doped graphene (NbN/NG) along the soluble polysulfides/electrolyte is designed and constructed to regulate corresponding interface chemical reaction, which can afford long-range electron transfer surfaces, numerous strong chemisorption, and catalytic sites in a working lithium-sulfur battery. Both experimental and theoretical calculation results suggest that a new catalytic interface enabled by metal-like NbN with superb electrocatalysis anchored on NG is highly effective in regulating the blocked polysulfide redox reaction and tailoring the Li S nucleation-growth-decomposition process. Therefore, the Li-S batteries with multifunctional NbN/NG barrier exhibit excellent rate performance (621.2 mAh g at 3 C) and high stable cycling life (81.5% capacity retention after 400 cycles). This work provides new insights to promote Li-S batteries via multifunctional catalytic interface engineering.
多硫化物穿梭效应和缓慢的反应动力学阻碍了锂硫（Li-S）电池的实际应用。已发现引入功能性中间层来捕获和结合多硫化物可有效阻止多硫化物迁移。此外，可溶性多硫化物/电解质界面处的表面化学是锂硫电池的关键步骤，其中稳定循环取决于电解质中被阻断的多硫化物的吸附和再利用。设计并构建了一种由氮化铌/N掺杂石墨烯（NbN/NG）组成的多功能催化界面，沿可溶性多硫化物/电解质排列，以调节相应的界面化学反应，这可以在工作的锂硫电池中提供长程电子转移表面、大量强化学吸附和催化位点。实验和理论计算结果均表明，由锚定在NG上具有超电催化性能的类金属NbN形成的新型催化界面在调节被阻断的多硫化物氧化还原反应和定制Li-S成核-生长-分解过程方面非常有效。因此，具有多功能NbN/NG阻挡层的锂硫电池表现出优异的倍率性能（3C时为621.2 mAh g）和高稳定循环寿命（400次循环后容量保持率为81.5%）。这项工作通过多功能催化界面工程为推动锂硫电池发展提供了新的见解。
