The electrodes of a fuel cell are the sites where the electrical energy conversion takesudplace and they are considered as the heart of the proton exchange membrane (PEM) fueludcell. This work is aimed at preparation of these electrodes using locally availableudmaterials which are carbon nanotubes and platinum. Carbon nanotubes were synthesizedudusing Swirled Floating Chemical Catalyst Vapour Deposition (SFCCVD) andudconventional chemical vapour deposition (CVD) methods developed by Iyuke andudCoville respectively. The SFCCVD method was used to produce various carbonudnanomaterials such as nanoballs, nanofibres, diamond particles, and carbon nanotubesudusing acetylene gas carbon source and ferrocene as an iron catalyst precursor. Theudhorizontal CVD reactor was used mainly to produce carbon nanotubes using acetyleneudgas as carbon source and a bi–metallic catalyst of iron and cobalt on a calcium carbonateudsupport. The SFCCVD reactor was optimized and various carbon nanomaterials wereudproduced at different experimental conditions of pyrolysis temperature, flow rate ofudacetylene, hydrogen and argon gases. A maximum production rate of 0.35 g/min wasudobtained at 1000oC, acetylene flow rate of 370 ml/min, hydrogen flow rate of 180 ml/minudand a flow ratio of acetylene to hydrogen equal to five. This production rate allows forudthe future scale up of this equipment. These carbon nanotube samples were purified andudfunctionalized with a mixture of concentrated H2SO4 and HNO3, and used as support for audplatinum catalyst using K2PtCl4 as platinum source and ethyl glycol as a reducing agent.udThe resultant catalyst samples are thermally stable up to 400oC and have platinumudparticles uniformly distributed on the CNTs with average size range between 1 and 8 nm.udThe various loadings of platinum on this carbon support were determined using UVudspectroscopic analysis of the filtrate before and after impregnation on the carbonudmaterial. A parametric study of the adsorption of platinum particles on CNTs indicatesudthat an increase in stirring time and temperature increases the amount of platinum loadedudon the CNTs. The cyclic voltammetric analysis of the resultant catalyst revealed thatudthese catalyst samples showed electrocatalytic activity for both hydrogenation andudoxygen reduction reactions. These catalyst samples were evenly cast on the carbon paperudto make electrocatalytic electrodes which were subsequently bonded to a sulphonatedudmembrane using a hot press method using constant conditions of temperature, pressureudand time, to produce the membrane electrode assembly (MEA). The performance of theudfabricated MEA was tested in a single PEM fuel cell using hydrogen as the fuel gas andudoxygen as oxidant. Analysis of the results obtained shows that the cell performanceudincreases with increase in platinum loading on the electrodes. A maximum voltage of 718udmV at 11.8 mA/cm2 was recorded for the highest platinum loading. A Hitchenhofer’sudequation was used to model the performance of the electrode in the cell.
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