Novel mesoporous graphitic carbon nitride modified PbBiO₂Br porous microspheres with enhanced photocatalytic...

Sustainable mesoporous graphitic carbon nitride (mpg-C₃N₄) modified PbBiO₂Br porous microsphere (mpg-C₃N₄/PbBiO₂Br) had been successfully synthesized via solvothermal process. Multiple techniques were applied to explore the structure, morphology, optical and electronic properties of the as-prepared photocatalysts. It could be found that the mpg-C₃N₄ was uniformly distributed on the surface of the PbBiO₂Br porous microsphere. Compared with the pure PbBiO₂Br, the mpg-C₃N₄/PbBiO₂Br exhibited superior photocatalytic activity for the degradation of organic pollutants under visible light irradiation. When the mass fraction of mpg-C₃N₄ was 3%, the mpg-C₃N₄/PbBiO₂Br composite materials exhibited the highest photocatalytic performance. The results indicated that the introduction of mpg-C₃N₄ could effectively enhance the electron mobility to promote the catalytic activity. The enhanced photocatalytic activity of the mpg-C₃N₄/PbBiO₂Br materials can be attributed to the stronger optical trapping capability and the more effective separation efficiency of photogenerated electron-hole pairs. During the process of photocatalysis, the main active species of the photocatalysts were determined to be the and hole under visible light irradiation. Based on the relative band positions of mpg-C₃N₄ and PbBiO₂Br, a possible photocatalytic mechanism of mpg-C₃N₄/PbBiO₂Br composite catalyst was proposed.