MOFs as sulfur storage materials in Li-S batteries
作者单位：Beijing National Laboratory for Molecular Sciences （BNLMS）The State Key Laboratory of Rare Earth Materials Chemistry and ApplicationsCollege of Chemistry and Molecular EngineeringPeking University
会议名称：《中国化学会第九届全国无机化学学术会议》
会议日期：2015年
学科分类：0808[工学-电气工程] 081704[工学-应用化学] 07[理学] 08[工学] 0817[工学-化学工程与技术] 070303[理学-有机化学] 0703[理学-化学]
关 键 词：electrochemical energy storage Li-S batteries cathode materials porous materials sulfur hosts
摘 要：We present here the use of metal-organic frameworks（MOFs） as sulfur hosts in lithium-sulfur（Li-S） batteries. We first compared the host properties of four distinct MOFs（MIL-53, NH2-MIL-53, HKUST-1 and ZIF-8）, and studied the effects of the window size, shape, unsaturated metal sites and function groups of the MOF pores on performance（cycling stability and rate capacity）, and electrochemical kinetics（charge transfer and internal diffusion）. We successfully obtained an effective MOF host, ZIF-8, which gives the best cycling performance. Then we chose ZIF-8 as a prototype and selectively synthesized five sets of ZIF-8 with different particle sizes（from 20 nm to 1 μm） to systematically study the effect of the particle size of a porous host on battery performance. The results show that there is an optimal selection of particle size for a given host to maximize the utilization of sulfur without sacrificing the capacity retention.