Bio-Inspired 2D Nanochannels With Adaptive Gating for Intelligent Molecular Sieving

Area of Science:

• Materials Science
• Chemical Engineering
• Environmental Science

Background:

• Intelligent membranes with tunable properties are crucial for advanced water treatment.
• Existing membranes often lack the precise control needed for complex separation tasks.

Purpose of the Study:

• To create a bioinspired, adaptive membrane with programmable permeance and precise sieving capabilities.
• To investigate the pH-responsive behavior of a novel graphene oxide-sodium alginate (GO-SA) composite membrane.

Main Methods:

• Constructed 2D nanochannels by incorporating sodium alginate (SA) chains into graphene oxide (GO) laminates.
• Investigated the conformational changes of SA chains and their effect on nanochannel size.
• Evaluated membrane performance in terms of water permeance and molecular sieving response factor.
• Studied the effect of calcium ions (Ca2+) on membrane stability and responsiveness.

Main Results:

• The GO-SA membrane exhibited high water permeance (122.67 L m⁻² h⁻¹ bar⁻¹) and a significant sieving response factor (50.12).
• The membrane demonstrated pH-responsive, adaptive regulation of channel size for selective molecular transport.
• Calcium ions were found to stabilize the membrane structure, "locking" its pH-responsive behavior.

Conclusions:

• The developed GO-SA membrane offers outstanding molecule sieving performance and programmable permeance.
• This bioinspired strategy provides a pathway for designing intelligent membranes with gated responses for complex water treatment.
• The system enables multistage dye separation and recovery/recycling of acids and alkalis.