Welcome to a new edition of #MeetOurPartners! On this occasion, we are introducing our researcher Sapir Willdorf-Cohen, who works at the Israel Institute of Technology (Technion), developing membranes for ANEMEL cells and stacks.
Membranes make the hearth of our electrolysers. Without them, the electrochemical reactions would simply stop working. “They serve as the bridge that connects the electrodes and enables the transportation of ions in the device,” says Willdorf-Cohen.
Our researcher developed an interest in this crucial component early on. During her bachelor’s degree in chemical engineering, she already conducted a research project on the stability of new anion exchange membranes. This phase of her studies took place in Darios Dekel’s group, the Technion Electrochemical Energy based on Membranes (TEEM) lab, where she has continued her research to this day. Notably, she completed her PhD under the supervision of Dario Dekel but also Charles Diesendruck, from the Chemistry Department at Technion.
“The focus of my PhD was to develop a method to estimate the real stability of functional groups and membranes, such as those used in fuel cells and water electrolysers. This research aimed to enhance key properties like ionic conductivity and chemical stability, ultimately helping the membrane perform better. Such advancements are crucial for clean energy applications,” she explains.
Willdorf-Cohen’s current role is lab engineering. She leads the effort of developing the functionalised ion exchange membranes and synthesising the membrane itself, using different methods. The objective: to develop and refine membrane compositions that are both efficient and long-lasting. But what exactly are we talking about?
The backbone of a membrane is a polymer. At ANEMEL, we have already observed that certain polymer composites improve membrane stability —membranes are exposed to extremely reactive and corrosive conditions during electrolysis, particularly when using seawater as a feedstock, as already a highly saline and oxidising environment. However, the polymers need some “extra spice”.
Willdorf-Cohen functionalises polymers to provide important properties for ion exchange membranes. In particular, the synthetic strategy involves introducing amine groups into the polymer itself to help the membranes retain more water and improve their ability to exchange hydroxide anions. This approach also ensures sufficient rigidity and resistance to corrosion, ultimately making the membranes more effective for electrolysis.
Initially, the approach resembled a literature review, examining “many different functional groups and cations,” says Willdorf-Cohen. “Some of them are commercially available, whereas others required two or three synthetic steps to achieve.” She plays with the temperature, the conditions, and other factors to fully perfect the process. “It’s taking time to optimise all of this,” she says.
Using different commercial functional groups, our researcher has “spiced up” some polymers from our partner in the University of Newcastle, in the UK — yes, we just love collaboration! “Now, we are testing the stability of the membranes, which seems good so far. For almost one month [of operation], we could not observe any decrease in stability under the conditions we used,” she explains. To test both stability and conductivity, Willdorf-Cohen has helped develop a new protocol to ensure that these membranes perform well under real-world conditions, which is crucial for their successful integration into energy systems.
This is not her only cross-team work. She closely collaborates with our partners on scaling up to make ion exchange membrane technology more cost-effective and available for large-scale clean energy solutions.
In this regard, Willdorf-Cohen is clear: “Green hydrogen, in my opinion, is a game changer for decarbonisation. It’s also a clean fuel that can be used in multiple sectors, such as transportation, industry, and power generation.”
