Intentionally added ionic surfactants induce Jones-Ray effect at air-water interface

Yuki Uematsu; Kengo Chida; Hiroki Matsubara

doi:10.1016/j.colcom.2018.10.003

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arXiv · 1810.01182

Intentionally added ionic surfactants induce Jones-Ray effect at air-water interface

Yuki Uematsu·Kengo Chida·Hiroki Matsubara

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Abstract

The Jones-Ray effect is an anomalous minimum in the surface tension of aqueous electrolytes at millimolar salt concentrations. We experimentally demonstrated that intentionally added ionic surfactants induce the Jones-Ray effect. The one-dimensional Poisson-Boltzmann theory, including the effect of surfactant adsorption and salt depletion, excellently agrees with the obtained experimental data. All the parameters of the ion-specific surface affinities used in the theory are consistent with previous experiments. These results strongly suggest that the Jones-Ray effect observed so far has been induced by the inevitable contamination of the air-water interfaces.

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Yuki Uematsu, Kengo Chida, Hiroki Matsubara. 2018-10-02. Intentionally added ionic surfactants induce Jones-Ray effect at air-water interface. https://doi.org/10.1016/j.colcom.2018.10.003

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