@article{8c3a8bb259af416baf3f88d7d5d0e8ea,
title = "Liquid-phase water isotope separation using graphene-oxide membranes",
abstract = "We report pressure-driven liquid-phase isotope separation (dead-end filtration) to enrich D and 18O in natural water using graphene oxide (G-O) and UV-reduced graphene oxide (UV-rG-O) membranes. The isotope diffusivity (molecular diffusion and adsorption separation) was found to be responsible for isotope separation. Adsorption separation is the dominant mechanism for improvements in D and 18O enrichment via increased G-O loading that leads to the increased number of adsorption sites (epoxy and hydroxyl groups on G-O), and higher degrees of reduction of G-O that result in the narrowing of the nanochannels which decreases the portion of water molecules experiencing molecular diffusion. The best performing membrane was “UV-rG-O” made by exposing a G-O membrane to 24 h UV irradiation from one side, showing enrichment of D of 0.5% for D/H and 18O of 0.08% for 18O/16O in a single-stage experiment, without contribution from the vapor pressure isotope effect. This work improves the understanding of the mechanisms for graphene-based membrane separation of D and 18O enriched water.",
keywords = "Diffusion, Filtration, Graphene oxide, Isotope effect, Membranes, Water isotopes",
author = "Karin Ching and Andy Baker and Ryoji Tanaka and Tingwen Zhao and Zhen Su and Ruoff, {Rodney S.} and Chuan Zhao and Xianjue Chen",
note = "Funding Information: The authors thank the staff at the Mark Wainwright Analytical Centre at the University of New South Wales (UNSW) for access to analytical equipment. A special thanks to Songyan Yin and Bill Bin Gong for the assistance in ToF-SIMS depth profiling. X.C. acknowledges Australian Research Council DECRA (DE180100294), UNSW Science Faculty Research Grants Program and AMP Tomorrow Fund for funding support. C.Z. is grateful for the award of a Future Fellow from the Australian Research Council (FT170100224). R.S.R. acknowledges the support by the Institute for Basic Science (IBS-R019-D1). Funding Information: The authors thank the staff at the Mark Wainwright Analytical Centre at the University of New South Wales (UNSW) for access to analytical equipment. A special thanks to Songyan Yin and Bill Bin Gong for the assistance in ToF-SIMS depth profiling. X.C. acknowledges Australian Research Council DECRA ( DE180100294 ), UNSW Science Faculty Research Grants Program and AMP Tomorrow Fund for funding support. C.Z. is grateful for the award of a Future Fellow from the Australian Research Council ( FT170100224 ). R.S.R. acknowledges the support by the Institute for Basic Science ( IBS-R019-D1 ). Publisher Copyright: {\textcopyright} 2021 Elsevier Ltd",
year = "2022",
month = jan,
doi = "10.1016/j.carbon.2021.10.009",
language = "English",
volume = "186",
pages = "344--354",
journal = "Carbon",
issn = "0008-6223",
publisher = "Elsevier Limited",
}