3D structured photocatalysts for sustainable H2O2 generation from saccharides derivatives

Abstract

The possibility of using hydrogen peroxide (H2O2) as a chemical oxidizer or as a green liquid fuel to produce electricity has encouraged both the scientific and industrial communities to investigate green technologies aimed at the sustainability of the production process. In particular, the light-induced synthesis of H2O2 from water and oxygen has attracted significant attention using optical semiconductors.An exfoliated metal-free graphitic carbon nitride material (GCN-T) was prepared and tested for the photocatalytic production of H2O2 using five saccharides (arabinose, cellobiose, fructose, glucose, and sorbitol) as sacrificial electron donors. The results showed that the scavenging efficiency of the photogenerated holes rapidly increases with the number of -OH groups in the molecular structure of these sacrificial agents. Among the polyhydroxy compounds tested, the highest concentration of H2O2 was achieved using cellobiose.To develop a technological approach for H2O2 production, the GCN-T photocatalyst was immobilized on a 3D printed structure (GCN-T/3D structure), which showed high stability with both ultrapure water and seawater after several reusability runs. This innovative photocatalytic structure enables remarkable efficiency for H2O2 production, with an apparent quantum efficiency (AQE) of 17% at 412 nm radiation, compared to 12% obtained with GCN-T in suspension.