Supramolecular immobilization of molecular catalysts on electrodes for solar fuel production

This dissertation investigates if supramolecular interactions can be used to assemble molecular components on electrodes, in particular for solar fuel production. In contrast to the current state of the art catalysts, which employ precious metals, the molecular components described in this thesis are based on abundant elements. We initially carried out fundamental studies to obtain a better understanding of the electrode components. We found that the limited charge conduction of the electrode material could hamper the overall performance of the electrode. Furthermore, we found that the performance of the catalyst we planned to use in the photoelectrode, depended on the conditions it is exposed to. These insights were valuable for the subsequent two chapters, where we assembled new photocathodes for the production of hydrogen and the conversion of carbon dioxide, using hydrophobic interactions. In the final chapter, we used a new approach based on a different supramolecular interaction (π–π stacking) to implement an iron-based molecular catalyst on a gas diffusion electrode, for the electrochemical conversion of carbon dioxide to carbon monoxide. Overall, we show in this thesis that supramolecular immobilization is a versatile strategy to include molecular catalysts on electrodes. We have shown here that we can install the state-of-the-art molecular first-row transition metal catalysts on (photo)electrodes via self-assembly, using hydrophobic interactions or π–π stacking. These novel electrodes were found to be active in (light-driven) proton and carbon dioxide reduction, underlining the wide applicability of supramolecular immobilization.