Dissertation
Artificial metallo-proteins for photocatalytic water splitting: stability and activity in artificial photosynthesis
Climate change is one of the largest challenges faced by humanity. To combat this research into alternatives to fossil fuels is ongoing. Dihydrogen is considered a good alternative fuel, since its burning only forms water.
- Author
- L.V. Opdam
- Date
- 26 March 2024
- Links
- Thesis in Leiden Repository
A promising means of acquiring dihydrogen is photocatalysis, which can be driven by sunlight. This involves water oxidation and proton reduction, both half-reactions require a catalyst and photosensitizer, generally metal complexes. The limited aqueous solubility and stability of these complexes poses a challenge in their application. In this thesis we investigated the use artificial metalloenzymes (ArMs) for the catalysis and photosensitization of both half-reactions. ArMs can improve the aqueous solubility of these catalysts and provide a second coordination sphere that can be used to improve the stability and activity. The ArMs in this thesis were prepared using the axial coordination of a catalyst or photosensitizer to a protein via histidine. We set up an effective screening method for this coordination using semi-native PAGE. We then prepared and characterized one of the first ArMs with photocatalytic water oxidation activity. We prepared eight photosensitizing ArMs, of which two also able to catalyse hydrogen evolution. Two of these ArM systems were entirely earth-abundant metal-based and showed good activity.