Ionic liquid-assisted synthesis and improved photocatalytic activity of p-n junction g-C3N4/BiOCl

The g-C3N4/BiOCl microsphere photocatalysts have been successfully synthesized in the presence of the reactable ionic liquid [C(16)mim] Cl. The p-n junction between p-type BiOCl and n-type g-C3N4 has been successfully constructed with g-C3N4 dispersed on the surface of BiOCl microspheres. The g-C3N4/BiOCl microspheres were characterized by XRD, XPS, SEM, FT-IR, and DRS. Rhodamine B (RhB) was used as a target pollutant to evaluate the photocatalytic activity of the as-prepared g-C3N4/BiOCl microsphere photocatalysts. The g-C3N4/BiOCl material exhibited superior photocatalytic performance when compared with pure BiOCl. The formed p-n junction was responsible for the improved separation efficiency of photogenerated electron-hole pairs, and thus the higher photocatalytic activity. The possible photocatalytic mechanism was proposed based on relative band positions of these two semiconductors.