In WP4 different series of composites have been synthesized for the photocatalytic reduction of CO2. MOF@Cu composites are based on different chemically stable Ti and Zr MOFs combined with CuOx and Cu0 nanoparticles (NPs) and nanoclusters (NCs). To optimize their visible light harvesting properties, MOF@Cu composites were combined with carbon quantum dots (CQDs) as photosensitizers. Also hydrophobic Zr MOFs have been employed to increase the CO2 adsorption capacity in presence of water. As shown by multiple advanced characterization tools (PXRD, N2 adsorption/desorption, ICP-OES, TGA, FT-IR, TEM, HAADF-STEM, XPS, electrochemical characterization), these composites presented a high crystallinity and porosity, good charge transfer kinetics.
In WP 3 the photophysical properties, the microstructural, (photo)electrochemical and CO2 adsorption properties of selected CO2RR and ORR materials developed in this project have been explored to identify key catalyst descriptors linked to their performances and provide design guidelines to improve and optimize material efficiency.
In WP5, the best Z-scheme heterojunctions without mediator (CuO@MIL-125(Ti)-NH2/Co@K-PHI, Cu2O@MIL-125(Ti)-NH2/Co@K-PHI, CuO@ UiO-66(Zr)-(CF3)2 /Co@K-PHI and Cu2O@ UiO-66(Zr)-(CF3)2 /Co@K-PHI; (5 wt.%)MOF@(95 wt.%)S-PHI using MIL-140B(Zr) and MIP-177(Ti)LT; several Cu species (e.g. Cu(II), CuO, Cu2O) grafted in MIP-177(Ti)-LT and their composites with Co-PHI) have been finally evaluated for the photocatalytic CO2 reduction to CH3OH under solar and visible light irradiation. The photocatalytic experiments have been optimized in terms of illumination conditions, CO2/H2O or H2 mol ratio, voltage and pressure. A novel photocatalytic reactor has been developed that is comprised of an asymmetric membrane that separates between the two half reactions. It uses copper NPs supported on MIL-125(Ti)-NH2 for CO2RR and Co-KPHI for OER, while decoupling between the transport of protons and the transport of electrons. Following illumination, several products were identified, in particular ethanol, methanol, C2H4 and other compounds, yet to be determined (suspected as formic acid/formaldehyde). In parallel, it was shown that in the absence of CO2, these products are not obtained, thus pointing out to the possibility of formation of fuels from CO2 by utilizing solar light.
Participation in several meetings and workshops related to Carbon Capture, Utilisation and Storage (CCUS) & Alternative Fuels., public perception and business models has been an excellent opportunity to network with industry experts, project representatives, investors and policy makers, facilitating collaboration, knowledge sharing and future partnerships. Participation in events such as conferences and workshops has enabled the development of relations with projects with similar research themes.
To foster the replicability and the transferability of the project’s solutions, two events on the International Industrial Board have been organized during the project, one in June 2023 with a progressed roadmap, and the other meeting at the end of the project in December 2024.