Xion Composite Bipolar Membranes

XION™ Composite Bipolar Membranes are ultra-strong, ultra-selective, and provide ultra-high performance, while demonstrating high chemical stability as reinforced bipolar membranes (BPM). Xergy has the largest selection of cation exchange ionomers (CEI) and anion exchange ionomers (AEI) to select from for various bipolar membrane (BPM) design.

A composite bipolar membrane is usually comprised of a mechanical reinforcement that is sandwiched between a cation exchange layer and an anion exchange layer.  Cation exchange layer (CEL) is formed by the cation exchange dispersion on one side of the mechanical reinforcement.  An anion exchange layer (AEL), on the other hand, is formed from the use of an anion exchange dispersion on the opposite side of the mechanical reinforcement. A composite bipolar membrane can also be called as composite bilayer membrane. Xergy's advanced production capability allows the design and manufacturing of various BPM configurations from a wide range of cation exchange ionomer (CEI) and anion exchange ionomer (AEI) materials. Ionomer materials are also known as dispersion materials in the fuel cell and electrolyzer industry.  CEIs available include Dyneon™, Aquivion™, and Nafion™ PFSA ionomers, and AEIs available include Pention™ ionomers. A microporous e-PTFE based reinforcement layer is integrated into the structure of the membrane to provide enhanced mechanical properties and reduced swelling. 

In the intermediate layer between Anion Exchange Layer (AEL) and Cation Exchange Layer (CEL), water is dissociated into OH- and H+ ions when exceeding a potential difference of approximately 0.8 V. The CEL must be directed towards the cathode, the AEL must be directed towards the anode, and the mode of operation has to be reverse biased in order to promote the water dissociation reaction.  Under the reverse biased mode, the electrons would be transferred from anode side to cathode side.  Water molecules would naturally diffuse into the intermediate layer between AEL and CEL and generation of H+ and OH- ions would occur as a result of water splitting reaction.  H+ ions will diffuse out from the CEL layer and migrate into the cathode chamber.  OH- ions, on the other hand, would diffuse out from the AEL layer and migrate into the anode chamber.

These are developmental products that are currently being offered to researchers for their various electrochemical applications and hence, the amount of experimental data is is scarce and Xergy team hopes that customers purchasing these products would provide some feedback in order to further improve their electrochemical performances.