Spiers Memorial Lecture: Breakdown of universality in angstrom-scale flows

Area of Science:

• Nanofluidics and molecular transport phenomena.

Background:

• Angstrofluidics investigates fluid and ionic transport in atomic-scale channels.
• Recent advances in carbon nanotubes, 2D materials, and lamellar membranes reveal exotic behaviors like anomalous dielectric responses, slip, and memristive transport.
• A unifying theoretical framework for angstrom-scale phenomena is currently lacking.

Purpose of the Study:

• To propose a unifying framework for understanding angstrom-scale fluid and ionic transport.
• To highlight the potential of angstrom-scale phenomena for advanced functionalities.
• To reframe the breakdown of universality as an opportunity for innovation.

Main Methods:

• Review and synthesis of recent advances in angstrom-scale fluidics.
• Theoretical analysis of transport phenomena at atomic dimensions.
• Conceptualization of new applications based on observed behaviors.

Main Results:

• Exotic transport behaviors, including anomalous dielectric responses, slip, and memristive effects, are observed in angstrom-scale channels.
• The apparent lack of universal behavior at these scales is identified as a key characteristic rather than a limitation.
• Angstrom-scale transport enables tailored non-linear responses and active ionic machines.

Conclusions:

• The unique transport phenomena at angstrom scales are an asset, not a drawback.
• Angstromfluidics offers a pathway to novel functionalities, including active ionic machines and neuromorphic nanofluidic architectures.
• A new framework is needed to fully exploit the potential of angstrom-scale transport.