The design of graphene-based (G) hybrid nano-materials for photocatalytic applications is one of the most promising routes in the field of water remediation1. Indeed, the combination of G with photoactive materials aims to strongly improve the photocatalytic performance of the formulated systems by boosting the separation and transfer of photo-generated charges, which constitutes a critical step in photocatalytic reactions. As it turns out, organic photosensitizers, which have an excellent visible-light (VL) absorption, coupled with the charge transfer properties of G-based materi-als (graphene, graphene oxide and reduced gra-phene oxide) represent cutting-edge water treat-ment technology. Moreover, the low cost, eco-friendliness, flexibility, and versatility of the mo-lecular design of these basic organic molecules constitute appealing features, both environmental-ly and economically. In this view, a freestanding hybrid nanocomposites by using high quality graphene 3D supported by Nickel foam and photoactive macromolecules was realized. The novelty of our approach consists in exploiting extensive non- covalent interactions between the high surface area of G co-catalyst by using a homo and copolycyclic polyporphyrins with and metal free (CPPrs). The unusual choice of CPPrs as photoactive sites is based on two assump-tions: i) their hindered conformational geometries might significantly avoid formation of agglomer-ates of single porphyrin units, that act the rapid quenching of excited state; ii) if compared to isolate photo-active molecules, polymers possess improved mechanical properties, being able to coat and protect the co-catalyst surface. Moreo-ver, our structure shows very high avalaible sur-face thanks to its foam structure, with clear ad-vantages in its PC performances. This new concept of GNPs formulation might avoid the shielding effect as well as the radical scavenger activity, maximizing the charge transfer process during photo-catalysis. The PCE of these GNPs were tested and compared to G/Pr units by photo-degrading MB dye in water under VL irradia-tion 2.
Materials based on 3D graphene and polyporphyrins for Visible-Light photocatalysis
Martina Ussia;Daniele Vitalini;
2018
Abstract
The design of graphene-based (G) hybrid nano-materials for photocatalytic applications is one of the most promising routes in the field of water remediation1. Indeed, the combination of G with photoactive materials aims to strongly improve the photocatalytic performance of the formulated systems by boosting the separation and transfer of photo-generated charges, which constitutes a critical step in photocatalytic reactions. As it turns out, organic photosensitizers, which have an excellent visible-light (VL) absorption, coupled with the charge transfer properties of G-based materi-als (graphene, graphene oxide and reduced gra-phene oxide) represent cutting-edge water treat-ment technology. Moreover, the low cost, eco-friendliness, flexibility, and versatility of the mo-lecular design of these basic organic molecules constitute appealing features, both environmental-ly and economically. In this view, a freestanding hybrid nanocomposites by using high quality graphene 3D supported by Nickel foam and photoactive macromolecules was realized. The novelty of our approach consists in exploiting extensive non- covalent interactions between the high surface area of G co-catalyst by using a homo and copolycyclic polyporphyrins with and metal free (CPPrs). The unusual choice of CPPrs as photoactive sites is based on two assump-tions: i) their hindered conformational geometries might significantly avoid formation of agglomer-ates of single porphyrin units, that act the rapid quenching of excited state; ii) if compared to isolate photo-active molecules, polymers possess improved mechanical properties, being able to coat and protect the co-catalyst surface. Moreo-ver, our structure shows very high avalaible sur-face thanks to its foam structure, with clear ad-vantages in its PC performances. This new concept of GNPs formulation might avoid the shielding effect as well as the radical scavenger activity, maximizing the charge transfer process during photo-catalysis. The PCE of these GNPs were tested and compared to G/Pr units by photo-degrading MB dye in water under VL irradia-tion 2.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
