This thesis focuses on the synthesis, characterization and performance towards CO2 electroreduction of mono and bi-metallic particles based on p-block metals. With an industrial perspective in mind... Show moreThis thesis focuses on the synthesis, characterization and performance towards CO2 electroreduction of mono and bi-metallic particles based on p-block metals. With an industrial perspective in mind, we try to synthesize particulate, high surface area materials with clean, scalable synthesis methods where possible and test their performance in H-Cell and gas diffusion electrode flow cell configurations. With a combination of characterization techniques, we find possible explanations for the catalytic behaviors. Show less
This dissertation focused on computational methods based on first principles calculations using the Density Functional Theory (DFT) framework. Emphasis was laid on affordable methods that can... Show moreThis dissertation focused on computational methods based on first principles calculations using the Density Functional Theory (DFT) framework. Emphasis was laid on affordable methods that can provide a tradeoff between computational expense and accuracy. Specifically, we investigated solvation effects near the surface of the electrode, used thermodynamic cycles to compute solution-phase energies and also proposed a workflow to detect gas-phase errors on the free energies of target molecules. We used these simple methods to study complex adsorption processes at the PdMLPt(111) electrode surface. DFT and experimental studies (performed by Dr. Chen from our group) were crucial to guide the investigation forward. Show less
With the energy transition toward a renewable energy supply and a CO2-neutral economy, electrification of the energy system is rising in importance, which leads to the challenge of long-term... Show moreWith the energy transition toward a renewable energy supply and a CO2-neutral economy, electrification of the energy system is rising in importance, which leads to the challenge of long-term storage of renewable electricity. A promising option is the electrochemical conversion of biomass or carbon dioxide in chemicals as energy carrier. In this research, catalysis of the electrochemical CO2 reduction was studied to obtain liquid fuels. In this fundamental study we discovered that so-called disproportionation reactions may occur simultaneously with the CO2 reduction reaction influencing the product spectrum. Moreover, we focused on metalloprotoporphyrins immobilized on a graphite surface. We found that the selectivity can be steered toward formic acid with rhodium, tin or indium metal centers. Apart from intrinsic catalyst parameters, we studied the influence of parameters related to the immobilization and the composition of the electrolyte. We showed that the substrate and its pretreatment as well as encapsulation of the catalyst in polymers can have a signifcant influence on the electrocatalysis of CO2 reduction. The results obtained in this thesis provide insight in the energy efficiency, reaction rate and selectivity of the CO2 reduction reaction, and play an important role for the development of an industrially viable process. Show less
