Towards accumulative charge-transfer in molecular photocatalysts for hydrogen production

• Applicant: Professor Dr. Dirk M. Guldi, since 7/2023
• Subject Area: Physical Chemistry of Molecules, Liquids and Interfaces, Biophysical Chemistry
• Term: since 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 491255400

The global goal of this project is to demonstrate the versatility of photon- and charge-management in novel electron donor-acceptor (D-A)-conjugates covalently-linked to catalytically active metal coordination complexes (CATs). This is meant to activate in the resulting ((D-A)-CAT)-conjugates the multi-electron reduction of the catalyst and to drive the molecular-controlled proton reduction for Solar H2 Generation under ultimately white light excitation. Our idea of building (D-A-CAT)s and ((D-A)-CAT-(A-D))s is beyond the general design concept for molecular H2 photocatalysts. We aim to activate CATs indirectly rather than directly, which could by-pass the rather large reorganization energy of catalytic centers, when photoinduced charge-separation occurs from photoexcited Ds directly to the CATs. A key point of our concept is the use of fullerenes and endohedral metallofullerenes as electron As and Ds, respectively. Advanced photophysical approaches including One-Color / One-Photon, One-Color / Two-Photons, and Two-Color / Two-Photons time-resolved experiments are planned to trigger charge-transfer and charge-shift reactions to CATs as a means to activate them. We expect to gain full control over the processes leading to the doubly-reduced CATs and to gain ideas of optimizing the dynamics of each charge-transfer / charge-shift event at the molecular level. The photophysical studies will be correlated with information on the performance of the (D-A-CAT)s or ((D-A)-CAT-(A-D))s conjugates, which will be evaluated by photocatalytic H2 generation activity as well as the long-term stability.

• DFG Programme: Research Grants
• Ehemalige Antragstellerin: Dr. Yusen Luo, until 6/2023