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arXiv · 2403.07163

Water Isotope Separation using Deep Learning and a Catalytically Active Ultrathin Membrane

Abstract

Water isotope separation, specifically separating heavy from light water, is a socially significant issue due to the usage of heavy water in applications such as nuclear magnetic resonance, nuclear power, and spectroscopy. Separation of heavy water from light water is difficult due to very similar physical and chemical properties between the isotopes. We show that a catalytically active ultrathin membrane (e.g., a nanopore in MoS2) can enable chemical exchange processes and physicochemical mechanisms that lead to efficient separation of deuterium from hydrogen, quantified as the D2O and deuterium separation ratio of 4.5 and 1.73, respectively. The separation process is inherently multiscale in nature with the shorter times representing chemical exchange processes and the longer timescales representing the transport phenomena. To bridge the timescales, we employ a deep learning methodology which uses short time scale ab-initio molecular dynamics data for training and extends the timescales to classical molecular dynamics regime to demonstrate isotope separation and reveal the underlying complex physicochemical processes.

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Jinu Jeong, Chenxing Liang, Narayana Aluru. 2024-03-11. Water Isotope Separation using Deep Learning and a Catalytically Active Ultrathin Membrane. https://doi.org/10.1039/d4cp04020a

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