Modulating g-C3N4 photocatalyst for H2 production via water splitting: The impact of Schiff base incorporation

This study explores the potential for improved photocatalytic activity by tailoring the properties of twodimensional graphitic carbon nitride (g-C3N4) through non-metallic molecule modifications. Herein, melamine monomers were thermally polymerized in the presence of organic materials, namely (E)-2-((phenylimino)methyl) phenol, (E)-4-(benzylideneamino)benzoic, and (E)-4-((hydroxybenzylidene)amino)benzoic acid, to produce g-C3N4-PMP, g-C3N4-BAB, and g-C3N4-HBAB nanosheet composites, respectively. The investigated Schiff bases offer a variety of functionalities capable of influencing the electronic structure, surface reactive sites, and porosity. Consequently, all of the modified composites exhibited higher efficiency in photocatalytic hydrogen generation compared to pristine g-C3N4. Notably, the highest catalytic activity was observed for g-C3N4-PMP, with a rate of 1148 mu mol.g(-1).h(-1) , which is seven times greater than that of g-C3N4. Optical and photo- electrochemical properties of the photocatalysts were analyzed to develop a workable mechanism for photo- catalysis. The utilization of organic Schiff bases in conjunction with melamine for the g-C3N4 synthesis presents a versatile approach to tailor the properties and augment the photocatalytic performance of the resulting nano-composite material for diverse environmental and energy-related applications.