Abstract
Il progetto PHOTOGEN mira alla fabbricazione di una cella fotoelettrochimica (PEC) per la reazione di splitting dell'acqua, in cui unità molecolari opportunamente progettate ed incorporate in un idrogel aerofobico lavorano in modo cooperativo assorbendo luce solare necessaria per la generazione di idrogeno e ossigeno all'interfaccia elettrodica. PHOTOGEN aimed at developing innovative molecular and hybrid photoelectrochemical systems for solar-driven water splitting, with the long-term goal of producing green hydrogen and oxygen directly from water using sunlight as the sole energy source. The project combined expertise in molecular synthesis, photophysics, electrochemistry, materials science, and photoelectrode engineering through the collaboration of the Universities of Messina, Bologna, and Ferrara. A key innovation was the integration of molecular photosensitizers and catalysts into functional hydrogel matrices and hybrid photoelectrodes, enabling controlled spatial organization of catalytic components, enhanced charge-transfer processes, and improved stability under operating conditions. The project addressed three main objectives: development of molecular systems for water oxidation, development of molecular catalysts for proton reduction, and fabrication of photoelectrodes and integrated architectures for future photoelectrochemical devices.
Results achieved
The project successfully delivered a broad set of scientific results covering molecular design, synthesis, characterization, and proof-of-concept functional testing. New ruthenium-based photosensitizers, molecular assemblies, water oxidation and proton reduction catalysts were synthesized and characterized through spectroscopic, electrochemical, and photophysical techniques. Specifically, novel catalyst–photosensitizer assemblies bearing vinyl functionalities were developed to enable incorporation into polymeric and hydrogel matrices. These systems exhibited broad visible-light absorption, retained catalytic activity, and demonstrated efficient photoinduced oxygen evolution. A major achievement was the development of an innovative photocatalytic hydrogel incorporating molecular water-oxidation assemblies. The hydrogel successfully produced oxygen under visible-light irradiation while protecting the molecular components from degradation. Compared with analogous homogeneous systems, the hydrogel showed enhanced operational stability, prolonged activity, recoverability after use, and evidence of successful covalent incorporation of the catalytic species within the polymer matrix. On the reduction side, a family of polymerizable cobalt-based catalysts was synthesized, including vinyl-functionalized cobaloxime derivatives suitable for future immobilization on cathodes. These compounds were obtained in good yields and thoroughly characterized, providing a robust platform for future hydrogen-evolution studies. The project also produced dye-sensitized photoanodes based on Ru(II) molecular dyes anchored to semiconductor surfaces. New sensitizers displayed efficient visible-light harvesting and generated photocurrents up to approximately 1 mA.cm-2 under illumination. Preliminary coupling of sensitizers with molecular water-oxidation catalysts on electrode surfaces demonstrated the feasibility of hybrid photoanode architectures, although further optimization of interfacial charge-transfer processes is required. Overall, PHOTOGEN established validated synthetic routes, generated new molecular components and functional materials, demonstrated light-driven oxygen production both in solution and in hydrogel matrices, and laid the foundations for future integration of photoanodes and photocathodes into complete solar-fuel devices.Project details
Unibo Team Leader: Andrea Fermi
Unibo involved Department/s:
Dipartimento di Chimica "Giacomo Ciamician"
Coordinator:
Università degli Studi di MESSINA(Italy)
Total Unibo Contribution: Euro (EUR) 60.855,00
Project Duration in months: 24
Start Date:
28/09/2023
End Date:
31/01/2026
