Fabricating Nano-Sized BiVO 4 /InVO 4 /g-C 3 N 4 Photocatalysts for Efficient Degradation of Acid Blue 92 Azo Dye

BiVO₄/InVO₄ and BiVO₄/InVO₄/g-C₃N₄ were prepared by hydrothermal and ultrasonic-assisted hydrothermal methods respectively. All prepared samples were characterised by X-ray diffraction, scanning electron microscopy and UV-Vis diffuse reflectance spectroscopy. The photocatalytic activity of the prepared catalysts was determined by degradation of Acid Blue 92 (AB92) under visible light. The rate constant and efficiency of AB92 degradation over BiVO₄/InVO₄/g-C₃N₄ was higher than that over BiVO₄/InVO₄ which indicates better photocatalytic activity of BiVO₄/InVO₄/g-C₃N₄. This enhancement can be attributed to the suitable dispersion of BiVO₄ and InVO₄ particles on the g-C₃N₄ surface. Furthermore, the conduction band and valence band edge potentials of InVO₄, BiVO₄ and g-C₃N₄ extend the life-time of electron–hole pairs which is beneficial for the improvement of photocatalytic efficiency.