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Updated: Jul 20, 2026

Merging Ion Concentration Polarization between Juxtaposed Ion Exchange Membranes to Block the Propagation of the Polarization Zone
Published on: February 23, 2017
Multispectral imaging of ion transport in neutral carrier-based cation-selective membranes
Robert E Gyurcsányi1, Ernõ Lindner
1Department of General and Analytical Chemistry, Budapest University of Technology and Economics, Szent Gellért tér 4, 1111 Budapest, Hungary.
Background:
High-resolution spectroscopic imaging of the cross section of ion-selective membranes during real-time electrochemical measurements is termed spectroelectrochemical microscopy (SpECM). SpECM is aimed for optimizing the experimental conditions in mass transport controlled ion-selective electrode (ISE) membranes for improved detection limit.
Methods:
The SpECM measurements are performed in a thin layer electrochemical cell. The key element of the cell is a membrane strip spacer ring assembly which forms a two compartment electrochemical cell. The cell is placed onto the stage of a microscope and the membrane strip is positioned in the center of the field of view. A slice of the image is focused onto the entrance slit of the imaging spectrometer.
Results:
SpECM has been used for the determination of the diffusion coefficients of different membrane ingredients and for the quantitative assessment of the charged site concentrations in ISE membranes and membrane plasticizers. In addition, changes in the concentration profiles of the ionophore (free and complexed) and charged mobile sites inside the ISE membranes are documented upon the application of large external voltages.
Conclusions:
This account demonstrates the power and advantages of SpECM, a multispectral imaging method for investigations of mass transport processes in ISE membranes during electrochemical measurements.
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