Enhanced Hydrogen Production by Photoreforming on C3N4 Adjusting Exfoliation and Platinum Co-Catalyst Dispersity

This article explores the optimization of C3N4 photocatalyst synthesis using different precursors such as melamine, urea, and dicyandiamide, evaluating the resulting morphology, structure and properties, aiming at improved hydrogen evolution by photoreforming of oxygenated substrates. Exfoliation methods, chiefly thermal annealing and ultrasonication coupled to fractionation, were explored to obtain thin nanosheets of high surface area. Adjustment of platinum co-catalyst photodeposition was performed to optimise Pt nanoparticle loading and maximise their dispersity on C3N4 nanosheets, resulting in enhanced photocatalytic efficiency. Hydrogen production activity from model oxygenated substances of increasing structural complexity that could be representative of wastewater components, such as methanol, glycerol, glucose or poly(ethylene glycol), was evaluated. This systematic study allows to gain insight into the relationship between photocatalytic hydrogen evolution and the composition of residual aqueous effluents.