Ricerc@Sapienza

An increasing energy demand connected with the replacement of fossil fuels and environmental concerns has made necessary the development of advanced and next-generation technologies for energy production. Between them, in the last years, fuel cells have received much attention, however, their practical application has to overcome the request for a high overpotential for the Oxygen Reduction Reaction (ORR) at the cathode. Among the approaches pursued to enhance the ORR process, the use of catalysts revealed to be the most effective. From previous studies, it is clear that the catalyst should be able to perform a 4-electrons reduction of O2. Generally, organometallic compounds consisting of a red-ox active transition metal cation stabilized by aromatic organic ligands have been applied. Despite being efficient catalysts for the ORR, the platinum-based compounds are very expensive. Although porphyrin, corrole and phtalocyanine-based ligands can be a valid alternative, their synthesis is frequently characterized by low yields, a feature which can hamper their production on industrial scale. While the proof of concept has been demonstrated, the potentiality of tetrapyrazinoporphyrazines derivatives has still to be explored. With the aim to study systematically the influence of substituents on the ORR selectivity, this project will be focused on the preparation of different tetrapyrazinoporphyrazine derivatives, their complexation with several low cost and environmental friendly transition metals and their adsorption on a solid support (nanotubes, reduced graphene oxide, carbon material). The compounds showing the most outstanding performances will be applied in fuel cells.