Novel Z-scheme heterogeneous photo-Fenton-like g-C3N4/FeOCl for the pollutants degradation under visible light irradiation

Effective electron-hole separation efficiency is an important factor for enhanced photocatalytic activity. In this work, the Z-scheme heterogeneous photo-Fenton-like (HPF-like) g-C3N4/FeOCl catalysts were synthesized successfully by calcination method. The composites were applied for the photo-Fenton (PF) degradation of water pollutants with the assistance of H2O2. During this process, the color-less antibiotic tetracycline and dye rhodamine B were used as the target pollutants. Compared with pure FeOCl material, the Z-scheme g-C3N4/FeOCl composites reveal a higher PF catalytic activity under the irradiation of visible light. According to the experimental results, the enhanced catalytic activity of g-C3N4/FeOCl material was attributed to the formation of Z-scheme between g-C3N4 and FeOCl, which could promote the separation efficiency of electron-hole pairs induced by hybridization. Moreover, with the addition of g-C3N4, the increased specific surface area would further promoted the decomposition of H2O2 to form more (OH)-O-center dot. The results of radical trapping experiments and ESR confirmed the hydroxyl radical was the main active group in this process, indicating the Z-scheme was generated between g-C3N4 and FeOCl. Therefore, a possible mechanism of this HPF-like g-C3N4/FeOCl material was presented. This work may promote the development and application of FeOCl-based materials in the field of PF-like water pollutants treatment.