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表面胺功能化增强氧化石墨烯膜的离子筛分
作者:小柯机器人 发布时间:2021/3/28 15:37:24

澳大利亚迪肯大学Weiwei Lei团队通过表面胺功能化增强氧化石墨烯膜的离子筛分性能。相关研究成果发表在 2021年3月24日出版的国际知名学术期刊《美国化学会杂志》。

由于二维(2D)纳米材料的膜以其优异的离子截留性能从盐水中提取淡水,在缓解全球淡水危机方面显示出巨大的潜力。然而,通过在亚纳米尺度内精确控制二维纳米材料膜的d间距来实现海水淡化的高选择性和高渗透性仍然是一个非常具有挑战性的问题。

该文中,研究人员开发了发展一种官能团修饰的氧化石墨烯(FGOMs) ,具体通过简单的一步plasma处理过程修饰有机胺等含氮基团、极性氮原子。氮官能团能与金属离子产生强烈的静电相互作用,使FGOMs在一元和二元溶液中的单/二价阳离子选择性分别达到90和28.3,是氧化石墨烯膜的10倍以上。

第一性原理计算证实了FGOMs的离子选择性是由金属离子与极化氮原子结合能的差异引起的。此外,厚度为50nm的超薄FGOMs在NaCl溶液中的截留率接近99.0%的情况下,具有高达120mol m–2h–1的纯化效率,显示出约4.31×103的超高水/盐选择性。

该简便高效的等离子体处理技术不仅为GOMs提供了一个很有前途的可持续水净化技术,包括离子分离和海水淡化,而且为实现特定用途的2D纳米材料膜的功能化提供了一种新的策略。

附:英文原文

Title: Enhanced Ion Sieving of Graphene Oxide Membranes via Surface Amine Functionalization

Author: Yijun Qian, Jing Shang, Dan Liu, Guoliang Yang, Xungai Wang, Cheng Chen, Liangzhi Kou, Weiwei Lei

Issue&Volume: March 24, 2021

Abstract: Membranes based on two-dimensional (2D) nanomaterials have shown great potential to alleviate the worldwide freshwater crisis due to their outstanding performance of freshwater extraction from saline water via ion rejection. However, it is still very challenging to achieve high selectivity and high permeance of water desalination through precise d-spacing control of 2D nanomaterial membranes within subnanometer. Here, we developed functionalized graphene oxide membranes (FGOMs) with nitrogen groups such as amine groups and polarized nitrogen atoms to enhance metal ion sieving by one-step controlled plasma processing. The nitrogen functionalities can produce strong electrostatic interactions with metal ions and result in a mono/divalent cation selectivity of FGOMs up to 90 and 28.3 in single and binary solution, which is over 10-fold than that of graphene oxide membranes (GOMs). First-principles calculation confirms that the ionic selectivity of FGOMs is induced by the difference of binding energies between metal ions and polarized nitrogen atoms. Besides, the ultrathin FGOMs with a thickness of 50 nm can possess a high water flux of up to 120 mol m–2 h–1 without sacrificing rejection rates of nearly 99.0% on NaCl solution, showing an ultrahigh water/salt selectivity of around 4.31 × 103. Such facile and efficient plasma processing not only endows the GOMs with a promising future sustainable water purification, including ion separation and water desalination, but also provides a new strategy to functionalize 2D nanomaterial membranes for specific purposes.

DOI: 10.1021/jacs.1c00575

Source: https://pubs.acs.org/doi/10.1021/jacs.1c00575

 

期刊信息

JACS:《美国化学会志》,创刊于1879年。隶属于美国化学会,最新IF:14.612
官方网址:https://pubs.acs.org/journal/jacsat
投稿链接:https://acsparagonplus.acs.org/psweb/loginForm?code=1000