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DOE OSTI · 1812112

Ion correlations drive charge overscreening and heterogeneous nucleation at solid–aqueous electrolyte interfaces

Abstract

Significance Ion distributions at charged solid–water interfaces, referred to as the electrical double layer (EDL), are poorly understood at high ion concentrations, in part due to the lack of molecular-scale descriptions of the interactions between adsorbed hydrated ions. Here, direct visualization of the salinity-dependent evolution of EDL structure reveals molecular origins of nonclassical transformation of the EDL, in which charge overscreening and heterogeneous nucleation are driven by ion–ion correlations at the interfaces. This manifestation of the atomistic basis of nonclassical behaviors provides a much-needed understanding of the impact of ion cooperativity at charged interfaces for the development of predictive models for element transport in natural environments and advanced technologies for material growth and synthesis in saline environments.

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Lee, Sang Soo, Koishi, Ayumi, Bourg, Ian C., Fenter, Paul. 2021-08-05. Ion correlations drive charge overscreening and heterogeneous nucleation at solid–aqueous electrolyte interfaces. https://doi.org/10.1073/pnas.2105154118

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36 MATERIALS SCIENCE↗