CAREER: Scalable Liquid Exfoliation Processing of Ultrathin Two-Dimensional Metal Dichalcogenides Nanosheets for Energy Storage Devices

职业：用于储能设备的超薄二维金属二硫化物纳米片的可扩展液体剥离加工

• 批准号: 1454151
• 负责人: Gurpreet Singh
• 金额: $ 50万
• 依托单位: Kansas State University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-02-01 至 2021-09-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1454151&HistoricalAwards=false
• 关键词: CAREER; Scalable; Liquid; Exfoliation; Processing

This Faculty Early Career Development (CAREER) Program grant will establish a novel process for large-scale production of atomically thin sheets of transition metal dichalcogenides (or TMDs) with optimized properties suitable for energy-based applications, specifically, rechargeable metal-ion batteries. TMD sheets possess several distinct functional properties that are not realized in their bulk crystalline form or in other widely studied layered materials such as pristine graphene and hexagonal boron nitride. One major hurdle currently impeding the commercial success of TMDs is lack of production at larger scales while maintaining desired chemical and physical attributes. This award supports fundamental research to provide needed knowledge for the development of a solution-based processing route that involves spontaneous exfoliation (i.e., separation into single molecular layers) of bulk crystals in strong acids. The new process will enable production of kilogram quantities of ultrathin TMD nanosheets, which would overcome major roadblocks and unlock a vast array of applications for these materials in the energy sector, ranging from inexpensive catalysts for hydrogen production to high performance rechargeable batteries and supercapacitors. Therefore, results from this research will promote the U.S. economy, environment, and quality of life of its citizens. This research spans across several disciplines including manufacturing, engineering mechanics, electrochemistry, and materials science. The inter-disciplinary approach will increase participation by underrepresented groups in laboratory research and positively impact engineering education.This project's solution-based approach can overcome challenges that current methods have such as low production rates of single layer sheets, scission of sheets into sub-micron sized particles, and long sonication times (hours to days). However, additional scientific barriers need to be overcome in order to unlock the full potential of exfoliated TMDs in the energy sector (for example, sodium-ion rechargeable batteries). These include, lack of basic science related to exfoliation mechanism(s); inability to manufacture large-area nanostructured TMD electrodes with desired fracture properties; and unexplored mechanism(s) of TMD/metal-ion intercalation and conversion chemistry. This project aims to fill-in these knowledge gaps by (1) performing experiments and developing theoretical formulations to explain the dominant mechanisms for spontaneous exfoliation of bulk TMDs into ultrathin sheets, (2) assessing the processing advantages of exfoliated sheets by interfacing with graphene (thinnest and strongest electrical conductor) to form composite electrodes, thereby testing the limits of nanostructuring on fracture strength and electrochemical storage capacity, and (3) combining novel in-situ and ex-situ experimental techniques with companion computational models to establish TMD/metal-ion intercalation chemistry and phase transition mechanisms.

这项学院早期职业发展(Career)计划拨款将建立一种大规模生产过渡金属二卤化物(或TMD)原子薄片的新工艺，该工艺具有适合于基于能源的应用，特别是可充电金属离子电池的优化性能。TMD薄板具有几个独特的功能特性，这些特性是其块状晶体形式或其他广泛研究的层状材料(如原始石墨烯和六方氮化硼)无法实现的。目前阻碍TMD商业成功的一个主要障碍是缺乏更大规模的生产，同时保持所需的化学和物理特性。该奖项支持基础研究，为基于溶液的处理路线的开发提供必要的知识，该路线涉及在强酸中块状晶体的自发剥离(即分离成单分子层)。新工艺将能够生产公斤级的超薄TMD纳米片，这将克服主要障碍，并开启这些材料在能源领域的广泛应用，从廉价的制氢催化剂到高性能充电电池和超级电容器。因此，这项研究的结果将促进美国的经济、环境和公民的生活质量。这项研究跨越了几个学科，包括制造、工程力学、电化学和材料科学。这种跨学科的方法将增加代表不足的群体对实验室研究的参与，并对工程教育产生积极影响。该项目的基于解决方案的方法可以克服当前方法存在的挑战，如单层片材的生产率低、片材分裂成亚微米大小的颗粒、以及较长的超声波处理时间(几小时到几天)。然而，需要克服更多的科学障碍，以释放能源部门剥离的TMD(例如，钠离子充电电池)的全部潜力。这些问题包括缺乏与剥离机理相关的基础科学(S)；无法制造具有所需断裂性能的大面积纳米结构TMD电极；以及TMD/金属离子插层和转化化学的未知机理(S)。本项目旨在通过以下方式填补这些知识空白：(1)进行实验并开发理论公式来解释块状TMD自发剥离成超薄片的主要机制，(2)通过与石墨烯(最薄和最强的导电体)形成复合电极来评估剥离片的加工优势，从而测试纳米结构对断裂强度和电化学存储能力的限制，以及(3)将新颖的原位和非原位实验技术与配套的计算模型相结合，建立TMD/金属-离子插层化学和相变机制。

项目成果

A sulfur host based on silicon oxycarbide for advanced lithium‑sulfur batteries

• DOI: 10.1016/j.est.2023.108388
• 发表时间: 2023-11
• 期刊: Journal of Energy Storage
• 影响因子: 9.4
• 作者: M. M. Amaral-M.;S. B. Mujib;Érick A. Santos;J. Ribeiro;H. Zanin;Gurpreet Singh