Kim Gyu Won, Lee Minwoo, Bae Jihong, Han Jihoon, Park Seokmin, Shim Wooyoung
Department of Materials Science and Engineering, Yonsei University, Seoul, 120-749, Korea.
Center for Multi-Dimensional Materials, Yonsei University, Seoul, 03722, Korea.
Nano Converg. 2024 Dec 12;11(1):54. doi: 10.1186/s40580-024-00465-y.
The growing demand for lithium, driven by its critical role in lithium-ion batteries (LIBs) and other applications, has intensified the need for efficient extraction methods from aqua-based resources such as seawater. Among various approaches, 2D channel membranes have emerged as promising candidates due to their tunable ion selectivity and scalability. While significant progress has been made in achieving high Li/Mg selectivity, enhancing Li ion selectivity over Na ion, the dominant monovalent cation in seawater, remains a challenge due to their similar properties. This review provides a comprehensive analysis of the fundamental mechanisms underlying Li selectivity in 2D channel membranes, focusing on the dehydration and diffusion processes that dictate ion transport. Inspired by the principles of biological ion channels, we identify key factors-channel size, surface charge, and binding sites-that influence energy barriers and shape the interplay between dehydration and diffusion. We highlight recent progress in leveraging these factors to enhance Li/Na selectivity and address the challenges posed by counteracting effects in ion transport. While substantial advancements have been made, the lack of comprehensive principles guiding the interplay of these variables across permeation steps represents a key obstacle to optimizing Li/Na selectivity. Nonetheless, with their inherent chemical stability and fabrication scalability, 2D channel membranes offer significant potential for lithium extraction if these challenges can be addressed. This review provides insights into the current state of 2D channel membrane technologies and outlines future directions for achieving enhanced Li ion selectivity, particularly in seawater applications.
锂离子电池（LIBs）及其他应用中锂的关键作用推动了对锂需求的不断增长，这加剧了从海水等水基资源中高效提取锂的需求。在各种方法中，二维通道膜因其可调的离子选择性和可扩展性而成为有前景的候选者。虽然在实现高锂/镁选择性方面取得了重大进展，但提高锂离子对海水中主要单价阳离子钠离子的选择性仍然是一个挑战，因为它们的性质相似。本综述全面分析了二维通道膜中锂选择性的基本机制，重点关注决定离子传输的脱水和扩散过程。受生物离子通道原理的启发，我们确定了影响能垒并塑造脱水与扩散相互作用的关键因素——通道尺寸、表面电荷和结合位点。我们强调了利用这些因素提高锂/钠选择性以及应对离子传输中抵消效应带来的挑战方面的最新进展。尽管已经取得了重大进展，但缺乏指导这些变量在渗透步骤中相互作用的综合原理是优化锂/钠选择性的关键障碍。尽管如此，凭借其固有的化学稳定性和制造可扩展性，如果能够解决这些挑战，二维通道膜在锂提取方面具有巨大潜力。本综述深入探讨了二维通道膜技术的现状，并概述了实现增强锂离子选择性的未来方向，特别是在海水应用方面。
