​Membranes that change their pore size in response to external stimuli, such as pH, heat and light, are set to transform separation science and technology. Such smart membranes developed by KAUST researchers display tunable pore size, which means they can selectively separate compounds according to their size when exposed to different light wavelengths.

Covalent organic networks (CONs) have recently emerged as metal-free potential alternatives to conventional membrane materials, such as metal-organic and zeolitic frameworks. These lightweight crystalline porous nanomaterials, which result from organic molecular building blocks held together by strong covalent bonds, are stable in aqueous and organic solvents. They also present a well-defined topology and pore size, which makes them attractive for applications in many fields, including gas adsorption and separation, energy storage and conversion, optoelectronics, chemical sensing and drug delivery. However, these structural features cannot be altered, which restricts the membranes’ applicability.

Click here to read the full story

Image: The study describes light-responsive smart membranes.
© SteveUnit4 / Shutterstock