Synthesizing carbon and Ceria supported Pd electrocatalysts for Alcohol Fuel Cell Systems
Musa, Suhail Ahmed
Introduction: A fuel cell is based on a rather simple design (hence the popularity of use in various industries) and is made up of multiple components tightly pressed together to form the unit –commonly referred to as the Membrane Electrode Assembly or MEA. The key components that a fuel cell is made up off includes but is not limited to: gas diffusion electrodes (GDEs) –alternatively referred to as the anode and cathode chambers; electrolyte –ion carrier/transporter from one electrode to the other (solid or liquid); electrically conducting wire; electro-catalyst –catalyst used to speed up one or more half reactions; the gasses used –although not technically a component of the fuel cell, they are required in order to function. The focus of this research lies with the electro-catalyst. The basic principle of a fuel cell is converting chemical energy into electricity. This is accomplished by a REDOX reaction –An electron (e-) is extracted from the alcohol (fuel –typically hydrogen based) and passed through an external circuit, generating a minor current, and flows to the other GDE where it combines with oxygen. The site at which both extraction and attachment of the electron occurs, is the catalytic surface –usually platinum. The by-product that is formed in this process is water –which made up of the oxygen present in the cathode bonding with the H+ ions passing through the electrolyte and e-through the external circuit. This is explained in greater detail in sections 1 and 2. Expendable/primary cells are those cells that have one life and after they are depleted, they are discarded. Secondary cells on the other hand have life cycles –that is, they can be used until depletion then recharged or refuelled with reactants so that they may serve their purpose again (thus being cycled multiple times) ...
A dissertation submitted to the Faculty of Engineering and the Built Environment, University of the Witwatersrand, in partial fulfilment of the requirements for the degree of Master of Science in Engineering, 2021