Collaborative Research: CDS&E: Computational Exploration of Electrically Conductive Metal-Organic Frameworks as Cathode Materials in Lithium-Sulfur Batteries

由锂金属阳极和地球上丰富的硫阴极组成的锂硫电池（LSB）作为一种有前途的储能候选者受到了广泛关注。迄今为止，一些挑战和技术障碍阻碍了LSB的发展。在这个合作项目中，Farnaz Shakib教授（新泽西理工学院）和Mohammad Momeni教授（密苏里大学堪萨斯城分校）将研究导电金属有机框架（EC-MOFs）作为LSB阴极材料的设计和应用。EC-MOFs是一种新型的纳米多孔材料，具有非常高的表面积和分层结构，可以承受电池工作期间的机械变形。该项目将通过采用新的计算技术来设计和研究一类新材料作为阴极的功能来推进科学。这将导致设计更有效的清洁能源。在这个项目中，研究生将被培训为STEM未来的熟练劳动力。本科生和K-12水平的学生将通过全天工作坊和暑期学校学习计算化学的基础知识，这将有助于他们在STEM领域的发展。尽管对锂硫电池（LSB）进行了深入的研究，但找到一种具有高导电性的多孔阴极材料，可以防止硫穿梭到阳极仍然是一个紧迫的挑战。该项目将解决Pi（π）堆叠的层状2D导电金属有机框架（EC-MOFs）作为LSB中最佳阴极材料的独特结构和电子特性。除了导电性的明显优势外，EC-MOFs的分层结构可以承受极端的变形而不会发生机械塌陷。同时，它们的多孔性质允许活性硫材料在阴极中的有效包封，从而提供增强的抵抗其溶解到电解质溶液中的阻力（穿梭效应）。该项目的主要目标是探索EC-MOFs几乎无限的化学空间，以引入理想的候选材料作为阴极材料。由于逐个分析数千种EC-MOFs作为潜在阴极材料是不切实际的，因此本研究遵循两个主要目标：（i）使用自动晶体结构创建工具创建全面且可扩展的EC-MOFs数据库，随后将高通量筛选发现具有所需结构和电学性质的EC-MOFs;和（ii）研究硫（S8）及其锂-多硫化物衍生物在电极处的包封和可能的传输。该奖项反映了NSF的法定使命，并已被认为是值得通过使用基金会的智力价值和更广泛的影响审查标准。

Lithium-sulfur batteries (LSBs) consisting of a lithium metal anode and an earth-abundant sulfur cathode have attracted much attention as a promising candidate for energy storage. To date, several challenges and technical hurdles prevent the development of LSBs. In this collaborative project, Professors Farnaz Shakib (New Jersey Institute of Technology) and Mohammad Momeni (University of Missouri–Kansas City) will investigate the design and application of electrically-conductive metal-organic frameworks (EC-MOFs) as cathode materials for LSBs. EC-MOFs are a new class of nanoporous materials with exceptionally high surface area and layered structures that can tolerate mechanical deformations during battery operation. This project will advance science by employing novel computational techniques to design and investigate the functionality of a new class of materials as cathodes. This will lead to the design of more efficient clean energy resources. During this project, graduate students will be trained as the skilled workforce for the future of STEM. Undergraduate and K-12 level students will learn the fundamentals of computational chemistry through full-day workshops and Summer Schools, which will help their growth in STEM fields.Despite intensive research on lithium-sulfur batteries (LSBs), finding a porous cathode material with a high electrical conductivity that can prevent sulfur shuttling to the anode is still a pressing challenge. The project will address the unique structural and electronic properties of Pi(𝜋)-stacked layered 2D electrically conductive metal-organic frameworks (EC-MOFs) as optimal cathode materials in LSBs. Apart from the apparent advantage of electrical conductivity, the layered architecture of EC-MOFs can endure extreme deformations without mechanical collapse. At the same time, their porous nature allows for efficient encapsulation of the active sulfur material in the cathode providing enhanced resistance toward its dissolution into the electrolyte solution (the shuttling effect). The primary goal of this project is to probe the virtually unlimited chemical space of EC-MOFs to introduce ideal candidates as cathode materials. Since a case-by-case analysis of thousands of EC-MOFs as potential cathode materials is impractical, this research follows two main objectives: (i) creating a comprehensive and expandable database of EC-MOFs with an automated crystal structure creation tool which will be followed by high-throughput screening discovery of EC-MOFs with desired structural and electrical properties; and (ii) investigating sulfur (S8) and its lithium-polysulfide derivatives’ encapsulation and possible transport at the electrode-electrolyte interface from advancedmolecular dynamics simulations.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.