Investigating the effects of chemical composition and surface structure of catalysts on the electrochemical reduction of carbon dioxide [electronic resource]
- Toru Hatsukade.
- Physical description
- 1 online resource.
- Hatsukade, Toru.
- Jaramillo, Thomas Francisco, primary advisor.
- Bao, Zhenan, advisor.
- Nørskov, Jens K., advisor.
- Stanford University. Department of Chemical Engineering.
- The elimination of our dependence on fossil fuel sources is strongly motivated by the non renewable nature of these resources and the mounting evidence of their connection to anthropogenic climate change. Such a shift away from the use of fossil fuels could be facilitated by the electrochemical reduction of CO2, as it could allow for a sustainable process by which renewable energy from wind and solar are used directly in the production of fuels and chemicals. However, one key barrier to its utilization is the lack of effective catalysts that make the process energy efficient and selective. In order to develop effective catalysts for the process, fundamental understanding of the catalytic reaction must be established. To this end, the relation between catalyst properties and catalytic performance was investigated in this thesis. In order to obtain fundamental insights into the chemical processes occurring at the catalyst surfaces during CO2 electroreduction, we first investigated a broad group of transition metals. The potential-dependent activity and selectivity of CO2 electroreduction on each metal were characterized, which allowed for the observation of trends across the metals investigated. Using these results and theory, key factors affecting the catalytic performance for CO2 electroreduction were elucidated along with insights for the design of better catalysts. The catalyst property-performance relation was further probed through surface modification schemes such as alloying and surface structure engineering. Key observations from these investigations include: the enhancement in the activity for CO2 electroreduction to further reduced products on a AgZn alloy compared to pure Ag and pure Zn, the composition dependence of the catalytic performance of a PdxIny alloy system, and the surface structure-dependence of the product selectivity among further reduced products on Cu thin films. These results highlight the importance of control over chemical composition and surface structure of the catalyst surface, and contribute toward the design of effective catalysts.
- Publication date
- Submitted to the Department of Chemical Engineering.
- Thesis (Ph.D.)--Stanford University, 2016.