School of Physics and Technology , University of Jinan , Jinan , Shandong 250022 , China.
School of Physics , Shandong University , Jinan , Shandong 250100 , China.
ACS Appl Mater Interfaces. 2018 May 2;10(17):15012-15020. doi: 10.1021/acsami.8b00942. Epub 2018 Apr 23.
Despite the high theoretical capacity of lithium-sulfur (Li-S) batteries, their commercialization is severely hindered by low cycle stability and low efficiency, stemming from the dissolution and diffusion of lithium polysulfides (LiPSs) in the electrolyte. In this study, we propose a novel two-dimensional conductive metal-organic framework, namely, Cu-benzenehexathial (BHT), as a promising sulfur host material for high-performance Li-S batteries. The conductivity of Cu-BHT eliminates the insulating nature of most S-based electrodes. The dissolution of LiPSs into the electrolyte is largely prevented by the strong interaction between Cu-BHT and LiPSs. In addition, orientated deposition of LiS on Cu-BHT facilitates the kinetics of the LiPS redox reaction. Therefore, the use of Cu-BHT for Li-S battery cathodes is expected to suppress the LiPS shuttle effect and to improve the overall performance, which is ideal for practical application of Li-S batteries.
尽管锂硫（Li-S）电池具有很高的理论容量，但由于其在电解质中溶解和扩散的多硫化锂（LiPSs），其商业化严重受到循环稳定性和效率低下的限制。在本研究中，我们提出了一种新型二维导电金属有机骨架，即 Cu-苯六噻吩（BHT），作为一种很有前途的高容量硫宿主材料用于高性能 Li-S 电池。Cu-BHT 的导电性消除了大多数基于 S 的电极的绝缘性质。Cu-BHT 与 LiPSs 之间的强烈相互作用，在很大程度上阻止了 LiPSs 溶解到电解质中。此外，LiS 在 Cu-BHT 上的定向沉积有利于 LiPS 氧化还原反应的动力学。因此，预计使用 Cu-BHT 作为 Li-S 电池的阴极可以抑制 LiPS 穿梭效应并提高整体性能，这对于 Li-S 电池的实际应用是理想的。
