@article{2ec4dc77fdcd492d9227e8a4c33a8a39,
title = "Design of Sub-Nanochannels between Graphene Oxide Sheets via Crown Ether Intercalation to Selectively Regulate Cation Permeation",
abstract = "Graphene-based membranes are a promising candidate for separating pollutants and ions. In particular, graphene oxide (GO) membranes are widely studied due to their unique nanochannels. The characteristic nanochannels of GO membranes can be manipulated via intercalation of cations, inhibiting the transport of other ions in the diffusion process. To maintain the tailored nanochannel during a pressure-assisted filtration procedure, it is essential to retain such inserted cations. Here, dibenzo-18-Crown-6 molecules (DB18C6) tightly binding to potassium ions are intercalated into GO nanosheets for preventing the leakage of the potassium ions from the nanochannel in the separation process. The complex between potassium ion and DB18C6 forges sub-nanochannels between GO nanochannels, controlling the salt rejection rate as well as the permeation of water molecules, and selectively inhibiting the transport of Na+ ions compared to the untreated GO membrane. The as-prepared GO@Crown composite membranes exhibit excellent NaCl rejection rates (up to 60%), water permeance (3.11–8.86 LMH bar−1), and a Na+ rejection rate (up to 62.5%) as well as an outstanding Na2SO4 rejection rate (up to 88%) in the dead-end filtration process. Molecular dynamics compute the tunable interlayer spacing of GO@Crown composite membranes and the possible configuration of crown ethers between GO layers, supporting the experimental results.",
keywords = "cation permeation, crown ether intercalation, desalination, graphene oxide, graphene-based membranes, membrane separation, nanochannels",
author = "Bang, {Ki Ryuk} and Daniel Bahamon and Vega, {Lourdes F.} and Cho, {Eun Seon}",
note = "Funding Information: This work is developed in the framework of a collaborative bilateral project between the Korea Advanced Institute of Science and Technology and Khalifa University of Science and Technology. This research was supported by the KAI-NEET Institute, KAIST, Korea, and also by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2018R1D1A1B07048233). Additional partial support of this work was provided by Khalifa University of Science and Technology through project RCII-2019-007. Computational resources from the Research and Innovation Center on CO2 and H2 at Khalifa University are also acknowledged. Funding Information: This work is developed in the framework of a collaborative bilateral project between the Korea Advanced Institute of Science and Technology and Khalifa University of Science and Technology. This research was supported by the KAI‐NEET Institute, KAIST, Korea, and also by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (2018R1D1A1B07048233). Additional partial support of this work was provided by Khalifa University of Science and Technology through project RCII‐2019‐007. Computational resources from the Research and Innovation Center on CO and H at Khalifa University are also acknowledged. 2 2 Publisher Copyright: {\textcopyright} 2020 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim",
year = "2020",
month = apr,
day = "1",
doi = "10.1002/admi.201901876",
language = "British English",
volume = "7",
journal = "Advanced Materials Interfaces",
issn = "2196-7350",
publisher = "John Wiley and Sons Ltd",
number = "8",
}