Photo-/Electro-chemical CO2-recycling: from disposal to resource

The most distressing task of Anthropocene is to find an effective process to convert renewable feedstocks of otherwise disposable materials into exploitable, cheap fuels and chemicals viasunlight-driven processes. Thisproject targets theproduction of small, transportable molecules with high energy content,starting from CO2as raw material. The overarching goalistosimultaneously targetthemitigation of climate change and the principles of circular economy.The strategy is based on the synergistic actionof orthogonal photo-and electro-catalysts able to drive the photoelectrochemical (PEC) conversion of CO2. In particular, an array of metal-coordinating porphyrin-derivatives with appended amine groups has been synthesized and tested in homogeneous phase as plausible electrochemical (EC) catalyst,1whereas organometallic Mo-/Mn-based complexes bearing terminal amino moieties have been tested as photosensitizers (PS).2A screening of the selectedporphyrinsshowed a promising ECbehaviour. Cyclic voltammetry data exhibit values of standard reduction potential (E°) for these molecules between -1.155 and -0.097 eV, i.e., compatible with CO2reduction. Further, the photochemical and photophysical characterization of the substrates suggeststhe possibility toexploit both catalysts simultaneouslywithout facing electron transfer (ET) processes.These preliminary results suggest the possibility to covalently link the tested molecules on an inert matrix in order to performheterogeneous catalysis in view of a further optimization and scalability of the system