Colloidal superionic conductors

Lin, Yange; Olvera de la Cruz, Monica

doi:10.1073/pnas.2300257120

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Colloidal superionic conductors

Lin, Yange·Olvera de la Cruz, Monica

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Abstract

Nanoparticles with highly asymmetric sizes and charges that self-assemble into crystals via electrostatics may exhibit behaviors reminiscent of those of metals or superionic materials. Here, we use coarse-grained molecular simulations with underdamped Langevin dynamics to explore how a binary charged colloidal crystal reacts to an external electric field. As the field strength increases, we find transitions from insulator (ionic state), to superionic (conductive state), to laning, to complete melting (liquid state). In the superionic state, the resistivity decreases with increasing temperature, which is contrary to metals, yet the increment decreases as the electric field becomes stronger. Additionally, we verify that the dissipation of the system and the fluctuation of charge currents obey recently developed thermodynamic uncertainty relation. Our results describe charge transport mechanisms in colloidal superionic conductors.

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37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY Applied Physical Sciences Colloidal Crystals Colloidal crystals Dissipation Lane Formation Lane formation Physical Sciences Science & Technology Sublattice Melting Sublattice melting Thermodynamic Uncertainty Relations Thermodynamic uncertainty relations

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Lin, Yange, Olvera de la Cruz, Monica. 2023-04-05. Colloidal superionic conductors. https://doi.org/10.1073/pnas.2300257120

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