Collaborative Research: Selective Extraction of Lithium from Seawater using Structurally Modified Metal Oxide Layered Materials

锂是许多现代储能系统的重要组成部分，包括锂离子电池。随着清洁能源的转型，对这种关键矿物的需求正在迅速增长，并将很快以目前的速度超过锂的供应。陆上锂资源(例如矿石和卤水)的锂产量可能不足以满足预期的需求。海水是一种前景看好的丰富锂资源，但从海水中回收锂在技术上具有挑战性。目前的回收方法存在萃取能力低、难以从海水中发现的化学相似离子中选择性地分离锂离子以及高昂的操作成本等方面的限制。伍斯特理工学院(WPI)的滕晓伟(音译)教授和路易斯维尔大学(UL)的巴德里·纳拉亚南(Badri Narayanan)教授致力于通过开发用于使用电化学方法从海水中选择性提取锂的新型氧化锰层状材料来解决这些技术限制。研究人员将把材料合成和表征方法与电化学性能评估和原子计算模拟相结合，以揭示材料结构如何影响阳离子传输行为。研究方法介于化学工程、材料科学、计算化学和电化学之间，为本科生和研究生的跨学科培养提供了宝贵的机会。该项目还将支持外联活动，以增加高中生和教师的科学参与度。该项目旨在了解结构改性水钠锰矿(MnO2)层状材料中掺杂剂、缺陷化学、离子水化和离子传输之间的相互作用，以从海水中选择性地提取锂。该研究方法将结合湿化学合成、电化学实验、操纵面X射线表征和各种原子模拟技术，以确定基于MnO2的电极的关键特征：(A)在拒绝较大的竞争离子(如钠、镁)的同时有利于锂离子的插入；(B)在抑制竞争离子扩散的同时促进锂离子的传输动力学；以及(C)在宽操作电压窗口下实现高容量的锂离子提取，同时避免水的解离。将考察MnO2的结构、组成、缺陷浓度/分布、掺杂剂的性质、层间距以及合成条件。来自STEM代表性不足群体的本科生将被招募到WPI和UL实验室参与研究。将启动两个实验室之间的暑期本科生交流计划，以扩大学生对新技术概念和研究环境的接触。高中科学教师将被邀请完成一个为期七周的暑期研究项目，以开发实践的科学学习方法和材料，并提高学生的科学素养和参与度。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Lithium is a vital component of many modern energy storage systems, including lithium-ion batteries. Demand for this critical mineral is growing rapidly, coinciding with the clean energy transition, and will soon outstrip lithium supplies at the current rate. Lithium production from land-based lithium sources (e.g., ore and brine) may be insufficient to meet the anticipated demand. Seawater is a promising, plentiful source of lithium, but recovering lithium from seawater is technologically challenging. Current recovery methods are limited by low extraction capacity, difficulty selectively separating lithium ions from chemically similar ions found in seawater, and high operation costs. Professor Xiaowei Teng at Worcester Polytechnic Institute (WPI) and Professor Badri Narayanan at the University of Louisville (UL) aim to address these technological limitations by developing new classes of manganese oxide layered materials for the selective extraction of lithium from seawater using electrochemical methods. The investigators will integrate materials synthesis and characterization methods with electrochemical performance assessment and atomistic computational modeling to reveal how the material structure affects the cation transport behavior. The research approach lies at the interface of chemical engineering, materials science, computational chemistry, and electrochemistry, providing a valuable opportunity for cross-disciplinary training of undergraduate and graduate students. The project will also support outreach activities to increase the scientific engagement of high-school students and teachers. The project aims to understand the interplay between dopants, defect chemistry, ion-hydration, and ion transport in structurally modified birnessite (MnO2)-based layered materials on selective lithium extraction from seawater. The research approach will combine wet-chemistry synthesis, electrochemical experiments, operando X-ray characterization, and a variety of atomistic simulation techniques to identify the critical characteristics of MnO2-based electrodes that (a) favor insertion of lithium ions while rejecting the larger competing ions (e.g., sodium, magnesium), (b) promote kinetics of lithium-ion transport while suppressing diffusion of competing ions, and (c) enable high-capacity lithium-ion extraction at wide operation voltage windows while avoiding water dissociation. MnO2 structure, composition, defect concentration/distribution, nature of dopants, and interlayer distance, as well as synthesis conditions, will be examined. Undergraduate students from underrepresented groups in STEM will be recruited to participate in the research at the WPI and UL laboratories. A summer undergraduate student exchange program between the two laboratories will be initiated to broaden students’ exposure to new technical concepts and research environments. High-school science teachers will be invited to complete a seven-week summer research program to develop hands-on science learning pedagogy and materials and improve scientific literacy and engagement among their students.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.