Synthesis and photocatalytic activity of g-C₃N₄/BiOI/BiOBr ternary composites

A novel ternary composite photocatalyst (g-C₃N₄/BiOI/BiOBr) was prepared via a facile solvothermal method. The samples were characterized by powder X-ray diffraction, transmission electron microscopy, UV-visible diffuse reflection spectrometry, X-ray photoelectron spectrometry and photoluminescence measurements. Under irradiation with visible light, the g-C₃N₄/BiOI/BiOBr photocatalyst showed a higher photocatalytic activity than pure g-C₃N₄ and BiOI/BiOBr for the degradation of methylene blue. Among the hybrid photocatalysts, 3% g-C₃N₄/BiOI/BiOBr showed the highest photocatalytic activity for the degradation of MB. These results suggest that the heterostructure combination of g-C₃N₄, BiOI and BiOBr provides a synergistic effect through an efficient charge transfer process.