Development of capacitive deionisation electrodes: optimization of fabrication methods and composition
Loading...
Date
2017
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
University of the Western Cape
Abstract
The objective of this research was to optimize the fabrication methods for and compositions of
electrodes for the Membrane Capacitive Deionisation (MCDI) system. Two electrode
fabrication methods were developed, namely a spray coating- and a casting method. The
compositions of the electrodes were varied yielding a total of 14 different electrode in an
attempt to optimize the fabrication methods and compositions of the electrodes. Three activated
carbons were utilized in this study, TOB, YP50F and YP80F, these activated carbons have
different surface areas and porosity therefore were affected different by the materials added in
the ink. Carbon black and carbon nanotubes were used as conductivity additives to enhance the
conductivity of the electrodes. Lastly a polymer binder was added to increase the mechanical
integrity of the electrode, this polymer was typically PVDF. For some electrodes, PVDF was
replaced with ion exchange polymers in an attempt to provide ion conductive properties to the
electrodes. To establish the charge capacity of the electrodes Cyclic Voltammetry was used, BET analysis
evaluated the surface area and porosity of the raw materials and fabricated electrodes. Scanning
Electron Microscopy was used to verify surface morphology and uniformity. Ion adsorption
capacity measurements were performed using a specially designed MCDI cell.
The objectives of this study were achieved, the fabrication methods were optimized with the
casting method producing superior electrodes. Apart from fulfilling the research objectives, the
current research work generated significant scientific value by revealing how the production
method impacts the electrode's surface area and electrode adsorption capacity.
Description
Magister Scientiae - MSc (Chemistry)