Ultraviolet-water-induced angstrom-sized channels in membrane for precise ion sieving

Area of Science:

• Materials Science
• Chemical Engineering
• Nanotechnology

Background:

• Polymer membranes with angstrom-sized channels are crucial for precise ion separation.
• Existing methods face challenges in creating and controlling angstrom-sized channels in commercial polymer membranes.

Purpose of the Study:

• To develop a new strategy for creating tunable angstrom-sized channels in ion-tracked polymer membranes.
• To enhance ion separation performance beyond current polymer membrane capabilities.

Main Methods:

• Utilizing an ultraviolet-water (UV-W) process to generate hydroxyl radicals.
• Employing hydroxyl radicals to controllably modify polymer chains within ion tracks, forming angstrom-sized channels (2.9-7.8 Å).

Main Results:

• Achieved tunable channel sizes and charges in polymer membranes.
• Demonstrated high Li+ permeation rate (0.3 mol m-2 h-1) and Li+/Mg2+ selectivity (1024).
• Exceeded the performance benchmarks of existing polymer membranes for ion separation.

Conclusions:

• The UV-W strategy offers an accessible method for fabricating angstrom-sized channels in various polymers.
• This advancement holds significant potential for applications in clean energy technologies, particularly in ion separation processes.