Graphene-modified g-C3N4/ α-Fe2O3 systems for light-induced hydrogen generation

Abstract

Photocatalysis represents an advanced and efficient technology for harnessing light energy. The non-toxicity, affordability, and versatility of this technique render it particularly attractive for hydrogen production via water splitting. Nevertheless, the primary challenge lies in identifying materials capable of efficiently catalyzing the water splitting reaction upon exposure to light. This study presents the influence of the quantity of hematite and graphene on g-C₃N₄ in the context of hydrogen generation from methanol-water decomposition under UVC irradiation. Pure g-C₃N₄ exhibits the highest hydrogen generation efficiency. However, adding hematite decreases photocatalytic efficiency, likely due to the formation of a type II heterojunction between α-Fe₂O₃ and g-C₃N₄, which reduces the overall reduction capacity of the system. While incorporating graphene into the g-C₃N₄/α-Fe₂O₃ system enhances photocatalytic efficiency by improving electron mobility and prolonging the lifetime of photo-generated excitons, the highest yield was achieved with BUF10/GNP0.5. This research offers valuable insights into charge transfer and separation processes for photo-generated excitons within the g-C₃N₄/α-Fe₂O₃ and g-C₃N₄/α-Fe₂O₃/graphene systems in the context of light-induced hydrogen production.