Microstructural description of ion exchange membranes: The effect of PPy-based modification

Properties of ion exchange membranes (IEMs) both cationic and anionic were widely analysed before and after chemical. The modification aims to reduce the crossover phenomena typically observed in RFBs by incorporating polypyrrole (PPy) at the inner of commercial IEMs. In this work, we have explored...

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Bibliographic Details
Authors: Salmeron Sanchez, Ivan, Asenjo Pascual, Juan, Avilés Moreno, Juan Ramón, Ocón Esteban, Pilar
Format: article
Publication Date:2022
Country:España
Institution:Universidad Autónoma de Madrid
Repository:Biblos-e Archivo. Repositorio Institucional de la UAM
Language:English
OAI Identifier:oai:repositorio.uam.es:10486/704312
Online Access:http://hdl.handle.net/10486/704312
https://dx.doi.org/10.1016/j.memsci.2022.120771
Access Level:Open access
Keyword:Conductivity
Ion exchange membrane
Membrane modification
Micro-heterogenous model
Transport-structural parameters
Química
Description
Summary:Properties of ion exchange membranes (IEMs) both cationic and anionic were widely analysed before and after chemical. The modification aims to reduce the crossover phenomena typically observed in RFBs by incorporating polypyrrole (PPy) at the inner of commercial IEMs. In this work, we have explored the insight of membranes by structural and generalized conductivity considerations and its implications in terms of physicochemical characteristics. Transport Structural Parameters (TSP) have been obtained from the electrolyte concentration dependencies (NaCl, in this work). AEMs successfully increased their specific conductivity (between 2.5 and 3.9 times) whereas CEMs slightly decreased (between 1.3 and 2 times). This approach was useful for the description of membrane electro-transport by using the so-called two-phase model which considers an IEM as an heterophase system (particularly, gel and interstitial phase) and their arrangement. AEMs almost doubled increased whereas CEMs doubled decreased their internal microphase arrangement in terms of structural parameter (α). A modification of the established model was applied to the CEMs to better understand their specific behaviour after polymerization. Up to 3.5 times the diffusion coefficient was obtained in AEMs after PPy modification. Finally, based on TSP obtained we propose a microstructural description for the IEMs studied in this work