@article { author = {Ahmad, Muhammad and Hussain, Shabbir and Abid, Muhammad Amin and Mumtaz, Asad and Ibrar, Muhammad and Muhammad, Saz}, title = {Creating Bipolar Junction by Depositing Ultrathin Anion-Exchange Coating on CationExchange Membrane to Dissociate Water in Electrodialysis}, journal = {Journal of Membrane Science and Research}, volume = {8}, number = {1}, pages = {-}, year = {2022}, publisher = {FIMTEC & MPRL}, issn = {2476-5406}, eissn = {2476-5406}, doi = {10.22079/jmsr.2021.540358.1502}, abstract = {Ultrathin anion-exchange films have been created by employing layer-by-layer (LBL) deposition method. The LBL  deposited protonated poly(allylamine) (PAH)/poly(4-styrenesulfonate) (PSS) polyelectrolyte multilayers (PEMs) behave as  anionexchange films when PAH and PSS polyelectrolyte solutions are prepared in NaSCN as a supporting electrolyte (SE). Reflectance FTIR studies indicate that when PAH is prepared in 0.5 M NaSCN and PSS is prepared in 1 M NaSCN, the thickness of the film and the number of anion-exchange sites in the film are manifold greater than those in the film  fabricated from PAH and PSS polyelectrolytes when either of them is prepared in 0.5 M NaSCN. Transmembrane potential measurements were performed to measure the permselectivity of thus fabricated PEMs. These measurements indicate  that the fabricated films demonstrate high anion-exchange properties at neutral pH. However, the ion-exchange  character of the films switches from anions- to cations-exchange when pH of the surrounding solutions changes from 7  to 8.4. Diffusion dialysis results through the coated alumina membranes confirm such a change in the net charge of the  films with a change in the pH. Current density-voltage curve studies indicate plenty of formation of H+ and OHions  through water dissociation occurring at the interfacial bipolar junction created by depositing these anion-exchange  coatings on Nafion cation-exchange membrane (CEM). Donnan dialysis studies also indicate the formation of bipolar  junction through deposition of such films on cationexchange membranes. }, keywords = {Nafion,Anion-exchange Coatings,Layer-by-Layer deposition,Bipolar Junction,Water splitting}, url = {https://www.msrjournal.com/article_247479.html}, eprint = {https://www.msrjournal.com/article_247479_e44e0444b9b18f0a097eea641616b1c3.pdf} }