>Magister Scientiae - MSc / The purpose of this study was to develop a high performance-lower cost catalyst
to be applied in Direct Methanol Fuel Cells (DMFC). The study also aimed to
prepare plurimetallic supported platinum (Pt), platinum-ruthenium (PtRu),
platinum-ruthenium-vanadium (PtRuV) and platinum ruthenium-vanadium-iron
(PtRuVFe) upon multi-walled carbon nanotube (MWCNT) as well as upon multiwalled
carbon nanotube-titanium oxide (MWCNT/TiO2) supports. Platinum is
very active but prone to poisoning by carbon monoxide (CO), which may be
present in the fuel used in fuel cells. The focus on the use of methanol was
because of its better reaction kinetics, and better performance in direct methanol
fuel cells (DMFC) better than proton exchange membrane fuel cell (PEMFC).
When Pt is alloyed with another platinum group metals (PGM) the alloying
decreases the over-potential for reactions critical in the fuel cells. Proton exchange
membrane fuel cell (PEMFC) performance may be improved at low metal
loading, when supported pluri-metallic catalysts are applied since the trimetallic
catalysts may promote high catalyst utilisation. In practice, DMFC require
electrodes with a Pt loading to achieve acceptance fuel cell (FC) power
performance. The aim of this study was therefore the reduction of the catalyst
loading through further improvement of mass activity of Pt based catalysts by
partial substitution of the noble metal/metals, and the use of a carbon support that
will provide high surface area, good electrical conductivity and high stability.
MWCNT supported pluri-metallic (PtRuVFe,) and bimetallic (PtRu)
nanoparticles possessed characteristic of increased surface area, improved
electron transfer rate, enhance electro-catalytic activity and promoted stability.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:uwc/oai:etd.uwc.ac.za:11394/6571 |
| Date | January 2018 |
| Creators | Javu, Bulelwa Patricia |
| Contributors | Petrik, Leslie F. |
| Publisher | University of the Western Cape |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Rights | University of the Western Cape |
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