Two-dimensional adaptive membranes with programmable water and ionic channels

TL;DR

This paper demonstrates the creation of artificial two-dimensional membranes with programmable water and ion channels, enabling tunable permeability through environmental stimuli like pH and ion presence, mimicking biological adaptive functions.

Contribution

The work introduces a novel self-assembled heterostructure of graphene oxide and polyamine that forms ionic channels with controllable permeability based on specific component interactions.

Findings

Membranes exhibit regulated water and ion permeability.

Permeability can be tuned by pH and ion presence.

Membranes have programmable selectivity based on component interactions.

Abstract

Membranes are ubiquitous in nature with primary functions that include adaptive filtering and selective transport of chemical and molecular species. Being critical to cellular functions, they are also fundamental in many areas of science and technology. Of particular importance are the adaptive and programmable membranes that can change their permeability or selectivity depending on the environment. Here, we explore implementation of such biological functions in artificial membranes and demonstrate two dimensional self assembled heterostructures of graphene oxide and polyamine macromolecules, forming a network of ionic channels that exhibit regulated permeability of water and monovalent ions. This permeability can be tuned by a change of pH or the presence of certain ions. Unlike traditional membranes, the regulation mechanism reported here relies on specific interactions between the membranes internal components and ions. This allows fabrication of membranes with programmable, predetermined permeability and selectivity, governed by the choice of components, their conformation and their charging state.