The thesis contains a discussion on the subject of the Oxygen Reduction Reaction (ORR) on Pt-alloy nanoparticle catalysts in the Rotating Disk Electrode (RDE) method. An insight in some of the... Show moreThe thesis contains a discussion on the subject of the Oxygen Reduction Reaction (ORR) on Pt-alloy nanoparticle catalysts in the Rotating Disk Electrode (RDE) method. An insight in some of the difficulties of this method is given with proper solutions and compensations for these problems. Pt3Co, Au-core Pt3Fe-shell catalysts dispersed on carbon support, as well as the 3M Nanostructured Thin Film (NSTF) catalyst are analyzed and the ORR activities measured. For the Pt3Co catalyst, the particle size effect and the effect of catalyst pretreatment is determined. The significant durability enhancement of the gold-core Pt3Fe-shell catalyst is discussed. A novel pretreatment method for the NSTF catalyst is shown, as well as the significant increase in mass activity for the ORR compared to carbon-supported catalysts. The thesis ends with an insight in the cyclic voltammetry of a Pt (100) single crystal electrodein alkaline media and the effect of the pretreatment of the catalyst. Show less
This thesis describes the results of the fundamental research on the electro-oxidation of ethanol. In addition, the oxidation of intermediates in the ethanol electro-oxidation reaction, such as... Show moreThis thesis describes the results of the fundamental research on the electro-oxidation of ethanol. In addition, the oxidation of intermediates in the ethanol electro-oxidation reaction, such as acetaldehyde and adsorbed CO, has also been studied. The goal of this research is to provide deeper insight into the molecular level understanding of the mechanism, and how various operational parameters affect this mechanism. With these insights, the development of low temperature direct ethanol fuel cells (DEFC) can be advanced, since, ultimately, the goal of fundamental catalysis research is the rational design of new catalysts, for which the understanding of molecular mechanisms is of essential importance. The mechanism of the electro-oxidation reaction is investigated using electrochemical techniques, such as cyclic voltammetry and chronoamperometry, as well as in situ characterization techniques, such as surface enhanced Raman spectroscopy (SERS), Fourier transform infrared spectroscopy (FTIR) and online electrochemical mass spectrometry (OLEMS). Show less