Wetting of nanopores probed with pressure

TL;DR

This paper introduces a pressure-based method to study and control wetting and nanobubbles in solid-state nanopores, enhancing understanding of ion transport and improving membrane design.

Contribution

It presents a novel pressure-driven approach to probe and manipulate wetting and nanobubbles in nanopores, addressing limitations of electrical methods.

Findings

Pressure can effectively wet nanopores and control nanobubbles.

Pressure helps distinguish true transport signals from wetting artifacts.

Nanobubbles influence conductance, which can be modulated by pressure.

Abstract

Nanopores are both a tool to study single-molecule biophysics and nanoscale ion transport, but also a promising material for desalination or osmotic power generation. Understanding the physics underlying ion transport through nano-sized pores allows better design of porous membrane materials. Material surfaces can present hydrophobicity, a property which can make them prone to formation of surface nanobubbles. Nanobubbles can influence the electrical transport properties of such devices. We demonstrate an approach which uses hydraulic pressure to probe the electrical transport properties of solid state nanopores. We show how pressure can be used to wet pores, and how it allows control over bubbles in the nanometer scale range normally unachievable using only an electrical driving force. Molybdenum disulfide is then used as a typical example of a 2D material on which we demonstrate wetting and bubble induced nonlinear and linear conductance in the regimes typically used with these experiments. We show that by using pressure one can identify and evade wetting artifacts.