Prussian Blue decorated g-C3N4 – From novel synthesis to insight study on charge transfer strategy for improving visible-light driven photo-Fenton catalytic activity

Abstract

To overcome the limitations in the reversibility of Fe2+/Fe3+ in the Fenton reaction, a reasonable concept of the addition of photoinduced electron donors has been developed. In this study, a facile solid-state reaction has been used to synthesize composites of Prussian Blue and g-C3N4 as an effective catalyst in the photo-Fenton reaction for organic pollutants decomposition. As a result, the degradation efficiencies of Rhodamine B and Tetracycline under the photo-Fenton catalytic process are 94.1% and 84.3%, respectively, after 60 min of treatment. Therein, a step-scheme model of electron-hole transport accelerated by a built-in electric field was ascribed as the origin of the significant improvement in the catalytic performance of the composites. A reasonable pathway for charge carrier transfer was proposed and demonstrated by both experimental and calculation proofs. Furthermore, the theoretical calculation result indicates that the decomposition of H2O2 to hydroxyl radicals is preferable on Prussian Blue, while the g-C3N4 is considered an electron-generator. Additionally, the decomposition mechanism of organic pollutants under the photo-Fenton reaction of the composites was also investigated.