Li Zhen, Ma Zhaoling, Wang Yanyong, Chen Ru, Wu Zhenjun, Wang Shuangyin
State Key Laboratory of Chem/Bio-Sensing and Chemometrics, Provincial Hunan Key Laboratory for Graphene Materials and Devices, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.
State Key Laboratory of Chem/Bio-Sensing and Chemometrics, Provincial Hunan Key Laboratory for Graphene Materials and Devices, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082, China.
Sci Bull (Beijing). 2018 Feb 15;63(3):169-175. doi: 10.1016/j.scib.2017.12.018. Epub 2017 Dec 20.
Shuttle effect is one of the most serious disadvantages in lithium-sulfur battery which results in poor cycle performance and hinders the commercialization of Li-S battery. To reduce the dissolution of polysulfides into the electrolyte and prolong the cycling stability, nanoparticle-stacked metal nitride derived from layered double hydroxides (LDHs) as an interlayer was inserted between sulfur cathode and separator to confine polysulfides by physical and chemical interactions. Meanwhile, the surface of metal nitride will form an oxide passivation layer. The passivation layer possesses hydrophilic metal-O group and provides a polar surface for strong binding with polysulfide. What's more, the nanoparticles-stacked structure could immerge and retain electrolyte well, which could enhance the ability of promoting the electron exchange rate. The sulfur electrode with nanoparticle-stacked metal nitride interlayer has an excellent cycle performance owing to the interactions between metal nitride and polysulfides. The battery delivered an initial capacity of 764.6 mAh g and still possesses a capacity of 477.5 mAh g with the retention of 62.4% after 800 cycles.
穿梭效应是锂硫电池最严重的缺点之一，它会导致电池循环性能不佳，并阻碍锂硫电池的商业化。为了减少多硫化物在电解液中的溶解并延长循环稳定性，源自层状双氢氧化物（LDHs）的纳米颗粒堆叠金属氮化物作为中间层插入硫正极和隔膜之间，通过物理和化学相互作用来限制多硫化物。同时，金属氮化物表面会形成一层氧化物钝化层。该钝化层具有亲水性的金属-氧基团，并提供一个极性表面以与多硫化物牢固结合。此外，纳米颗粒堆叠结构能够很好地浸润并保留电解液，这可以增强促进电子交换速率的能力。由于金属氮化物与多硫化物之间的相互作用，具有纳米颗粒堆叠金属氮化物中间层的硫电极具有出色的循环性能。该电池的初始容量为764.6 mAh g，在800次循环后仍具有477.5 mAh g的容量，容量保持率为62.4%。
