Israeli, German researchers develop new method to produce membranes

A new method for fabricating membranes will provide a new, versatile and accurate tool for filtering particles.

 On the right: The fabrication process of the membranes. Metal oxides are grown within the membrane channels to precisely tunes the pore size, after which a reaction is generated to create a membrane possessing unique physical properties. On the left: Cross-sectional image of the membrane, showing t (photo credit: TECHNION SPOKESPERSON'S OFFICE)
On the right: The fabrication process of the membranes. Metal oxides are grown within the membrane channels to precisely tunes the pore size, after which a reaction is generated to create a membrane possessing unique physical properties. On the left: Cross-sectional image of the membrane, showing t
(photo credit: TECHNION SPOKESPERSON'S OFFICE)

Researchers from the Technion and Helmholz-Zentrum Hereon Center in Germany have developed a new method for fabricating membranes that can precisely filter various nanoparticles, according to a new paper published in Advanced Materials.

The study was led by Assistant Professor Tamar Segal-Peretz and Ph.D. student Assaf Simon of the Wolfson Faculty of Chemical Engineering at the Technion, along with Dr. Zhenzhen Zhang and Professor Volker Abetz of the Helmholz-Zentrum Hereon Research Center.

The membranes aim to synthetically mimic the high-selectivity molecular separation which takes place commonly in nature. In such separation, membrane channels separate the interior of a cell from its outside environment and regulate which materials can enter and exit the cell.

Creating such a membrane synthetically has faced difficulties, as fabricating a membrane with high levels of well-ordered pores and high uniformity and selectivity poses a complex engineering challenge, which is made even more complex when such membranes are intended for extremely small nanoparticle separation.

Despite the challenges, the Israeli and German researchers managed to succeed in fabricating such membranes using block copolymers — Spontaneously self-assembled polymer molecules, in combination with metal oxide growth on and within the pores of the block copolymer.

 (Right) Assistant Professor Tamar Segal-Peretz (Left) Assaf Simon (credit: TECHNION SPOKESPERSON'S OFFICE) (Right) Assistant Professor Tamar Segal-Peretz (Left) Assaf Simon (credit: TECHNION SPOKESPERSON'S OFFICE)

The process provides an excellent method for precisely tuning the pore size and other properties of the membrane. The metal oxide is also an ideal base for incorporating groups of atoms on the membrane surface with distinctive chemical properties, such as electric charge and hydrophobicity (water repellency).

Segal-Peretz estimated that the breakthrough will provide a number of industries with a new, versatile and accurate tool for the filtration of molecules, pollutants and other particles.