The force-flux relationship is a fundamental concept in explaining mass transport under a driving force in non-equilibrium conditions. This relationship is captured by the Onsager relation, which describes how gradients in concentration, temperature, and voltage drive the transport of mass, heat, and charge, while also considering crosseffects. In this presentation, I will explore how ion transport driven by a voltage gradient varies depending on the diffusion medium, and how this transport can be harnessed in various technological applications. Specifically, I will focus on layered materials with van der Waals gaps, which facilitate ion movement along pathways with low diffusion energy barriers. These materials hold significant potential in semiconductors, metals, and insulators, where they could serve as memory devices, switching devices, and ion-sieving membranes.

References

1. “Mapping cation-eutaxy ternary with a phenomenological model” Won, J. & Shim, W.* and coworkers, Nature Communications in-press

2. “Memristive InAs-based semiconductors with anisotropic ion transport” Kim, T. & Shim, W.* and coworkers,Advanced Materials 2500056

3. “Anomalous in-plane electrical anisotropy in elemental metal nanosheets” Kim, T. & Shim, W.*and coworkers, Nature Synthesis (2024)

4. “Cation-eutaxy enabled III-V-derived van der Waals crystals as memristive semiconductors” Bae, J., Won, J. & Shim, W.* and  

     coworkers, Nature Materials 23, 1402 (2024)

5. “Polytypic two-dimensional FeAs with high anisotropy” Won, J. & Shim, W.* and coworkers, Nano Letters 23, 23 (2023)

6. “Nontypical Wulff-shaped silicon nanosheets with high catalytic activity” Lee, M. & Shim, W.* and coworkers, J. Am. Chem. Soc. 145,

    22620 (2023)

7. “Layered Aluminum for electromagnetic wave absorber with near-zero reflection” Kim, T. & Shim, W.* and coworkers, Nano Letters 21,

    1132 (2021)

8. “Neuromorphic van der Waals crystals for substantial energy generation” Kim, S. & Shim, W.* and coworkers,

    Nature Communications 12, 47 (2021)