Fe@g-C3N4: an effective photocatalyst for Baeyer–Villiger oxidation under visible light condition

Abstract

In this work, we fabricated peculiar and highly cogent iron-doped graphitic carbon nitride (Fe@g-C₃N₄) nanocatalysts with varying ratios of g-C₃N₄ nanosheets to Fe-dopant in 1 : 1, 1 : 3, and 1 : 5, respectively. Numerous physicochemical techniques, including high-resolution transmission electron microscopy (HRTEM), Fourier transform infrared (FTIR), powder X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS) were used to validate the as-synthesized catalysts to explain their morphology and chemical structure. In addition, it was revealed that Fe metal ions were well disseminated with no alteration in the layered stacking structures of the g-C₃N₄ nanosheet and/or might interact with N atoms of the graphitic plane, forming intercalation compounds, thereupon influencing the energy band structure, augmenting visible light absorption, and electron–hole rupture rate. Under visible light (12 W) conditions, Fe@g-C₃N₄ (1 : 1) has shown superior performance for selective Baeyer–Villiger oxidation reaction, giving 100% cyclohexanone conversion and an admirable product selectivity of 2-oxepanone, i.e., 99.85%. Besides, the main advantages of the present catalyst include its excellent reusability up to five repeated cycles with no significant loss of activity.