Full Text Available

Note: Clicking the button above will open the full text document at the original institutional repository in a new window.

Fabrication of Catalyst Coated Membranes by Ultrasonic Spray for Proton Exchange Membrane Water Electrolysers

Renewable hydrogen, referred to as green hydrogen (GH), holds significant importance in the endeavour to decarbonise the transportation and industrial sectors. GH is generated via the electrochemical process of water splitting, utilising excess renewable energy sources such as solar and wind, thus s...

Full description

Saved in:
Bibliographic Details
Main Author: Mawungwe, Nyasha
Other Authors: Mohamed, Rhiyaad
Format: Thesis
Language:English
Published: Department of Chemical Engineering 2024
Subjects:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1867614160971366400
access_status_str Open Access
author Mawungwe, Nyasha
author2 Mohamed, Rhiyaad
author_browse Mawungwe, Nyasha
Mohamed, Rhiyaad
author_facet Mohamed, Rhiyaad
Mawungwe, Nyasha
author_sort Mawungwe, Nyasha
collection Thesis
description Renewable hydrogen, referred to as green hydrogen (GH), holds significant importance in the endeavour to decarbonise the transportation and industrial sectors. GH is generated via the electrochemical process of water splitting, utilising excess renewable energy sources such as solar and wind, thus serving as a sustainable means of energy storage. The production of GH can be done in a proton exchange membrane water electrolyser (PEMWE), by splitting water into hydrogen and oxygen utilising an important component called the catalyst-coated membrane (CCM). The CCM is composed of a membrane coated with noble metal-based catalyst nanoparticles that make up the anode and cathode electrodes. The sluggish anode kinetics and the elevated cost associated with the CCM have acted as barriers to the widespread acceptance of PEMWEs. In this study, we used ultrasonic spraying for catalyst coating. Previous research suggests that optimising these parameters can enhance PEMWE performance and commercial viability. The research conducted involved an ultrasonic spraying parameter variation and an anode catalyst loading study. The ultrasonic spraying variation investigated the nozzle height and nozzle speed. The anode catalyst ink was formulated from a commercial catalyst and applied to each membrane forming a half CCM, and thereafter, combined with a commercially developed cathode to form a full CCM. The CCMs were physically characterised, and electrochemically tested. The results were compared to assess the impact of ultrasonic spraying parameters and anode loading on performance and catalyst utilisation. The fabricated samples with approximately 2 mg Ir anode loading were further compared to a commercial CCM benchmark, considering the CL surface, microstructure, performance, and catalyst utilisation. The results showed the influence of spraying parameters, catalyst type, and loading on microstructure, performance, and utilisation. This showed the importance of optimising parameters and loading to develop comparable low-loaded catalyst layers to assist PEMWE adoption.
format Thesis
id oai:open.uct.ac.za:11427/39650
institution University of Cape Town (South Africa)
language eng
last_indexed 2026-06-10T12:47:38.275Z
license_str Not specified — see source repository
provenance_str_mv Harvested via OAI-PMH from UCTD — University of Cape Town Open Access Repository
publishDate 2024
publishDateRange 2024
publishDateSort 2024
publisher Department of Chemical Engineering
publisherStr Department of Chemical Engineering
record_format dspace
source_str UCTD — University of Cape Town Open Access Repository
spelling oai:open.uct.ac.za:11427/39650 Fabrication of Catalyst Coated Membranes by Ultrasonic Spray for Proton Exchange Membrane Water Electrolysers Mawungwe, Nyasha Mohamed, Rhiyaad Engineering Renewable hydrogen, referred to as green hydrogen (GH), holds significant importance in the endeavour to decarbonise the transportation and industrial sectors. GH is generated via the electrochemical process of water splitting, utilising excess renewable energy sources such as solar and wind, thus serving as a sustainable means of energy storage. The production of GH can be done in a proton exchange membrane water electrolyser (PEMWE), by splitting water into hydrogen and oxygen utilising an important component called the catalyst-coated membrane (CCM). The CCM is composed of a membrane coated with noble metal-based catalyst nanoparticles that make up the anode and cathode electrodes. The sluggish anode kinetics and the elevated cost associated with the CCM have acted as barriers to the widespread acceptance of PEMWEs. In this study, we used ultrasonic spraying for catalyst coating. Previous research suggests that optimising these parameters can enhance PEMWE performance and commercial viability. The research conducted involved an ultrasonic spraying parameter variation and an anode catalyst loading study. The ultrasonic spraying variation investigated the nozzle height and nozzle speed. The anode catalyst ink was formulated from a commercial catalyst and applied to each membrane forming a half CCM, and thereafter, combined with a commercially developed cathode to form a full CCM. The CCMs were physically characterised, and electrochemically tested. The results were compared to assess the impact of ultrasonic spraying parameters and anode loading on performance and catalyst utilisation. The fabricated samples with approximately 2 mg Ir anode loading were further compared to a commercial CCM benchmark, considering the CL surface, microstructure, performance, and catalyst utilisation. The results showed the influence of spraying parameters, catalyst type, and loading on microstructure, performance, and utilisation. This showed the importance of optimising parameters and loading to develop comparable low-loaded catalyst layers to assist PEMWE adoption. 2024-05-20T11:28:12Z 2024-05-20T11:28:12Z 2023 2024-05-20T11:17:21Z Thesis / Dissertation Masters MSc http://hdl.handle.net/11427/39650 eng application/pdf Department of Chemical Engineering Faculty of Engineering and the Built Environment
spellingShingle Engineering
Mawungwe, Nyasha
Fabrication of Catalyst Coated Membranes by Ultrasonic Spray for Proton Exchange Membrane Water Electrolysers
thesis_degree_str Master's
title Fabrication of Catalyst Coated Membranes by Ultrasonic Spray for Proton Exchange Membrane Water Electrolysers
title_full Fabrication of Catalyst Coated Membranes by Ultrasonic Spray for Proton Exchange Membrane Water Electrolysers
title_fullStr Fabrication of Catalyst Coated Membranes by Ultrasonic Spray for Proton Exchange Membrane Water Electrolysers
title_full_unstemmed Fabrication of Catalyst Coated Membranes by Ultrasonic Spray for Proton Exchange Membrane Water Electrolysers
title_short Fabrication of Catalyst Coated Membranes by Ultrasonic Spray for Proton Exchange Membrane Water Electrolysers
title_sort fabrication of catalyst coated membranes by ultrasonic spray for proton exchange membrane water electrolysers
topic Engineering
url http://hdl.handle.net/11427/39650
work_keys_str_mv AT mawungwenyasha fabricationofcatalystcoatedmembranesbyultrasonicsprayforprotonexchangemembranewaterelectrolysers