Shimizu Takeshi, Wang Heng, Matsumura Daiju, Mitsuhara Kei, Ohta Toshiaki, Yoshikawa Hirofumi
School of Science and Technology, Kwansei Gakuin University, 2-1 Gakuen, Sanda, Hyogo, 669-1337, Japan.
School of Material and Chemical Engineering, Zhengzhou University of Light Industry, Zhengzhou, 450002, P. R. China.
ChemSusChem. 2020 May 8;13(9):2256-2263. doi: 10.1002/cssc.201903471. Epub 2020 Mar 3.
Three porous disulfide-ligand-containing metal-organic frameworks (DS-MOFs) and two nonporous coordination polymers with disulfide ligands (DS-CPs) with various structural dimensionalities were used as cathode active materials in lithium batteries. Charge/discharge performance examinations revealed that only porous DS-MOF-based batteries exhibited significant capacities close to the theoretical values, which was ascribed to the insertion of electrolyte ions into the DS-MOFs. The insolubility of porous 3 D DS-MOFs in the electrolyte resulted in cycling performances superior to that of their 1 D and 2 D porous counterparts. Battery reactions were probed by instrumental analyses. The dual redox reactions of metal ions and disulfide ligands in the MOFs resulted in higher capacities, and the presence of reversible electrochemically dynamic S-S bonds stabilized the cycling performance. Thus, the strategy of S-S moiety trapping in MOFs and the obtained correlation between the structural features and battery performance could contribute to the design of high-performance MOF-based batteries and the practical realization of Li-S batteries.
三种具有不同结构维度的含二硫键配体的多孔金属有机框架材料（DS - MOFs）和两种含二硫键配体的无孔配位聚合物（DS - CPs）被用作锂电池的阴极活性材料。充放电性能测试表明，只有基于多孔DS - MOF的电池表现出接近理论值的显著容量，这归因于电解质离子插入到DS - MOFs中。多孔三维DS - MOFs在电解质中的不溶性导致其循环性能优于一维和二维多孔同类材料。通过仪器分析探究电池反应。MOFs中金属离子和二硫键配体的双重氧化还原反应导致更高的容量，并且可逆电化学动态S - S键的存在稳定了循环性能。因此，在MOFs中捕获S - S部分的策略以及所获得的结构特征与电池性能之间的相关性有助于高性能MOF基电池的设计以及锂硫电池的实际实现。
