Fabrication of N-Doped Carbon Quantum Dots/BiOI Nanocomposite and Its Efficient Photocatalytic Activity Under Visible-Light Irradiation

A novel spherical N-CQDs/BiOI photocatalyst was successfully synthesized through a facile solvothermal method. The optimization experiments of hydrothermal time and temperature were carried out. The effect of ammonium citrate addition was investigated. The as-synthesized photocatalysts were characterized via X-ray diffraction, scanning and transmission electron microscopy, Fourier transform infrared spectrum and elemental analysis. The adsorption and photocatalytic performance of as-synthesized photocatalysts were studied, 0.2N-CQDs/BiOI showed the best performance. For the removal of anionic dye RhB, adsorption occupied a major position. The maximum adsorption capacity was 97.09 mg/g for RhB. For the removal of cationic dyes X3B, photocatalysis occupied a major position. The photocatalytic activity of 0.2N-CQDs/BiOI was superior to that of nano-TiO 2 under the simulate sunlight irradiation. Different scavengers were used to analyze the effect of active species and photocatalytic degradation mechanism of X3B. The outstanding stability and performance make 0.2N-CQDs/BiOI has highly potential applications in wastewater treatment.