Photosensitized Switching of Norbornadienes Anchored to Copper Indium Sulfide Quantum Dots

• Applicant: Dr. Till Zähringer
• Subject Area: Inorganic Molecular Chemistry - Synthesis and Characterisation ; Solid State and Surface Chemistry, Material Synthesis ; Physical Chemistry of Solids and Surfaces, Material Characterisation
• Term: since 2026
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 582279194

The transition from fossil fuels to sustainable energy systems requires new strategies for capturing and storing solar energy. Molecular solar thermal (MOST) systems based on the norbornadiene/quadricyclane photoswitch are among the most promising molecular energy carriers because they convert sunlight into a stable, high-energy chemical form. However, existing MOST materials based on norbornadienes suffer from key limitations, insufficient efficiency, a reliance on ultraviolet light, and low energy-storage densities. These shortcomings prevent their practical use. This project targets a fundamentally new approach in which norbornadiene units are anchored to copper indium sulfide quantum dots (CIS-QDs). CIS-QDs absorb visible light across a broad spectral range and act as sensitizers, enabling the norbornadiene/quadricyclane conversion to proceed through an energy transfer pathway. This strategy allows the system to harvest the dominant portion of the solar spectrum. The choice of CIS is particularly advantageous due to its favorable and tunable photophysical properties and its non-toxic, earth-abundant composition, which aligns with the requirements for sustainable and scalable energy-storage materials. The project is structured into four components: (i) design and synthesis of norbornadiene ligands with tailored binding motifs for CIS-QDs; (ii) engineering of CIS-QDs with optimized surface and photophysical properties for efficient ligand attachment and sensitization; (iii) spectroscopic elucidation of the energy transfer step and the subsequent photoconversion; and (iv) development of proof-of-concept MOST materials capable of repeated measurable heat release. The expected outcomes will clarify the fundamental energy transfer mechanism across the quantum-dot-organic interface in these hybrid systems and demonstrate how this mechanism can be exploited to establish a new concept for environmentally compatible next-generation MOST materials. My expertise in molecular energy transfer and norbornadiene photo-switches is complemented by the experience of Professor Paola Ceroni, who will host this project and provide guidance in quantum dot synthesis and spectroscopy. Conducting this research under her supervision at the University of Bologna will lay the foundation for my independent research career and equip me with the skills needed to lead future research projects.

• DFG Programme: Fellowship
• International Connection: Italy
• Host: Professorin Dr. Paola Ceroni