MOFs及衍生复合材料在锂硫电池中的设计应用

在能源危机与环境问题日益凸显的背景下，电化学储能技术得到了迅速发展。在“超越锂”储能领域的竞争者中，锂硫电池(Li-S)因其具有高理论比容量、高质量能量密度并且环境友好、价格低廉等优点，成为最有前途的新储能技术。但是，锂硫电池的发展仍存在一些瓶颈问题需要解决，例如正极材料导电性能差、多硫化物穿梭效应及在充放电过程中电极体积膨胀等。作为锂硫电池的关键组成部分，电极和隔膜材料的设计和制备对解决这些问题及电池整体性能提升起到了重要的作用。金属有机骨架(MOFs)及衍生的复合材料作为锂硫电池电极或隔膜修饰材料，具有质量轻、电子和离子传导性好、孔道丰富和活性位点均匀分布等优势。此外，这类复合材料还具备形貌和组分可控、来源丰富和孔径可调等特性，从而便于机制研究。本文全面介绍了锂硫电池组成、工作原理并综述了近几年MOFs及衍生复合材料在锂硫电池中的研究进展，重点讨论了其在正极材料和隔膜材料中的应用，并对未来该材料在锂硫电池研究方向上的前景和突破进行了展望。 

Design and application of MOFs and derived composite materials inlithium-sulfur batteries

Against the background of increasingly prominent energy crisis and environmental problems, electrochemical energy storage technology has been developed rapidly. Among the competitors in the field of “beyond lithium” energy storage, lithium-sulfur batteries (Li-S) have become the most promising new energy storage technology owing to the advantages of high theoretical specific capacity, high mass energy density, environmental friendliness and low cost. However, there are still some bottleneck problems to be solved in the development of lithium-sulfur batteries, such as poor conductivity of cathode materials, polysulfide shuttle effect and electrode volume changes during charge and discharge. As the key components of lithium-sulfur batteries, the design and preparation of electrode and separator materials play the important roles in solving these problems and improving the overall performance of the batteries. Metal-organic frameworks (MOFs) and their derived composite materials exhibit the advantages of light weight, good electron and ion conductivity, abundant channels and uniform distribution of active sites to be used as electrode or separator modification materials for lithium-sulfur battery. In addition, this kind of composite material also possesses the characteristics of controllable morphology and composition, abundant source and adjustable pore size, which are convenient for mechanism research. Herein, we comprehensively introduce the composition, working mechanism and application of lithium-sulfur batteries. Importantly, we also review the research progress of MOFs and derivatives as cathode materials and separator materials in lithium-sulfur batteries in recent years. The prospects of the materials in improving the performance of lithium-sulfur batteries are also prospected.