RII Track-4: Electrochemical Modulation of Permeability and Selectivity of Conductive MXene Membranes

RII Track-4：导电 MXene 膜的渗透性和选择性的电化学调节

• 批准号: 1929195
• 负责人: Majid Beidaghi
• 金额: $ 18.38万
• 依托单位: Auburn University
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-12-01 至 2023-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1929195&HistoricalAwards=false
• 关键词: RII; Track; Electrochemical; Modulation; Permeability

The development of efficient membrane-based water desalination and purification technologies is essential for addressing the global challenges of water scarcity and pollution. An ideal separation membrane should show high permeance (transport of desired species) and high selectivity (rejection of undesired species), two properties that are often inversely correlated. In processes such as water desalination and removal of heavy metals from water, charged ions are separated from water by size exclusion or electrostatic interactions with a membrane. Two-dimensional (2D) materials are crystalline materials consisting of one or few layers of atoms and have attracted much interest in recent years for the fabrication of efficient membranes. Nanoporous or lamellar membranes based on 2D materials can potentially separate ionic species from water at higher rates and more efficiently compared to current membranes. The main goal of this project is to understand the effects of applied electrochemical potential on the separation performance of conductive membranes based on 2D transition metal carbides (MXenes). To achieve this goal, the PI will partner with researchers at Northeastern University to fabricate nanoporous and lamellar MXene membranes and study their separation properties. In addition, this project will provide opportunities to train graduate students in advanced membrane materials synthesis and characterization methods and will establish a long-term collaboration between Auburn University and Northeastern University. The PI will also integrate the result of this research into a recently developed course focused on applications of 2D materials. Electroactive membranes based on 2D MXenes can potentially separate metal ions and other charged species from water at higher rates and efficiencies compared to current membranes. This project will provide a scientific framework for designing electroactive nanoporous and lamellar membranes based on conductive 2D MXenes. Single-layer flakes of two different MXenes, Ti3C2 and Ti2C, will be synthesized and used for the fabrication of the membranes. Experimental measurement setups and procedures used in this project will enable accurate measurements of membrane properties to understand the effects of applied electrochemical potentials on the permeability and selectivity of the fabricated membranes. We hypothesize that by enhancing the charge exclusion mechanism of MXene membranes through an external electrochemical potential, membranes with larger nanochannels or nanopores but similar or better rejection properties can be designed. The research team will investigate the influence of the magnitude and sign of the applied potential on the selectivity of membranes towards various cations and anions in water. While this project is specifically focused on MXenes as membrane materials, its research plan addresses fundamental questions about the interactions of ions and charged membranes, and the results of the proposed research may apply to membranes fabricated using other 2D materials. The research results and conclusions will be disseminated through publications and presentations to both scientific and public audiences.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.

开发高效的膜法海水淡化和净化技术对于应对水资源短缺和污染的全球挑战至关重要。理想的分离膜应显示出高渗透性（所需物质的传输）和高选择性（不需要物质的排斥），这两种性质通常是负相关的。在诸如水脱盐和从水中去除重金属的过程中，带电离子通过尺寸排阻或与膜的静电相互作用从水中分离。二维（2D）材料是由一层或几层原子组成的晶体材料，并且近年来在制造高效膜方面引起了很大的兴趣。基于2D材料的纳米多孔或层状膜与当前的膜相比，可以更高的速率和更有效地从水中分离离子物质。本项目的主要目标是了解所施加的电化学势对基于二维过渡金属碳化物（MXenes）的导电膜的分离性能的影响。为了实现这一目标，PI将与东北大学的研究人员合作，制造纳米多孔和层状MXene膜，并研究其分离性能。此外，该项目还将为培养研究生提供先进的膜材料合成和表征方法的机会，并将建立奥本大学和东北大学之间的长期合作。PI还将把这项研究的结果整合到最近开发的专注于2D材料应用的课程中。与目前的膜相比，基于2D MXene的电活性膜可以以更高的速率和效率从水中分离金属离子和其他带电物质。该项目将为设计基于导电2D MXene的电活性纳米多孔和层状膜提供科学框架。将合成两种不同MXene（Ti3C2和Ti2C）的单层薄片并用于制造膜。在这个项目中使用的实验测量设置和程序将使膜性能的准确测量，以了解所施加的电化学电位对所制造的膜的渗透性和选择性的影响。我们假设，通过增强MXene膜的电荷排阻机制，通过外部电化学电位，可以设计具有更大的纳米通道或纳米孔，但类似或更好的排斥性能的膜。该研究小组将研究施加电势的大小和符号对膜对水中各种阳离子和阴离子的选择性的影响。虽然该项目特别关注MXenes作为膜材料，但其研究计划解决了有关离子和带电膜相互作用的基本问题，拟议研究的结果可能适用于使用其他2D材料制造的膜。研究结果和结论将通过出版物和演讲向科学和公众传播。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

项目成果

Conductive and highly compressible MXene aerogels with ordered microstructures as high-capacity electrodes for Li-ion capacitors

• DOI: 10.1016/j.mtadv.2021.100135
• 发表时间: 2021-03
• 作者: J. Orangi;H. Tetik;P. Parandoush;E. Kayali;D. Lin;M. Beidaghi

3D Printed MXene Aerogels with Truly 3D Macrostructure and Highly Engineered Microstructure for Enhanced Electrical and Electrochemical Performance

• DOI: 10.1002/adma.202104980
• 发表时间: 2021-11
• 期刊: Advanced Materials
• 影响因子: 29.4
• 作者: H. Tetik;J. Orangi;Guang Yang;Keren Zhao;S. B. Mujib;Gurpreet Singh;M. Beidaghi;D. Lin

2D Titanium and Vanadium Carbide MXene Heterostructures for Electrochemical Energy Storage

• DOI: 10.1016/j.ensm.2021.06.014
• 发表时间: 2021-06
• 期刊: Energy Storage Materials
• 影响因子: 20.4
• 作者: Armin VahidMohammadi;Wentao Liang;Mehrnaz Mojtabavi;M. Wanunu;M. Beidaghi