Enhanced Fenton, photo-Fenton and peroxidase-like activity and stability over Fe3O4/g-C3N4 nanocomposites

• Published in: Chinese journal of catalysis Vol. 38; no. 12; pp. 2110 - 2119
• Main Authors: Sahar, Shafaq, Zeb, Akif, Liu, Yanan, Ullah, Naseeb, Xu, Anwu
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.12.2017
• Subjects: Dopamine oxidation; Dye degradation; Fe3O4/g-C3N4 nanocomposites; Fenton reaction; Horseradish peroxidase mimicking; Peroxidase activity; Fenton reaction; Dye degradation; Horseradish peroxidase mimicking; Fe3O4/g-C3N4 nanocomposites; Peroxidase activity; Dopamine oxidation
• ISSN: 1872-2067; 1872-2067
• DOI: 10.1016/S1872-2067(17)62957-7

We prepared the Fe3O4/g-C3N4 nanoparticles (NPs) through a simple electrostatic self-assembly method with a 3:97 weight ratio to investigate their Fenton, photo-Fenton and oxidative functionalities besides photocatalytic functionality. We observed an improvement of the Fenton and photo-Fenton activities of the Fe3O4/g-C3N4 nanocomposites. This improvement was attributed to efficient charge transfer between Fe3O4 and g-C3N4 at the heterojunctions, inhibition of electron-hole recombination, a high surface area, and stabilization of Fe3O4 against leaching by the hydrophobic g-C3N4. The obtained NPs showed a higher degradation potential for rhodamine B (RhB) dye than those of Fe3O4 and g-C3N4. As compared to photocatalysis, the efficiency of RhB degradation in the Fenton and photo-Fenton reactions was increased by 20% and 90%, respectively. Additionally, the horseradish peroxidase (HRP) activity of the prepared nanomaterials was studied with 3,3,5,5-tetramethylbenzidinedihydrochloride (TMB) as a substrate. Dopamine oxidation was also examined. Results indicate that Fe3O4/g–C3N4 nanocomposites offers more efficient degradation of RhB dye in a photo-Fenton system compared with regular photocatalytic degradation, which requires a long time. Our study also confirmed that Fe3O4/g-C3N4 nanocomposites can be used as a potential material for mimicking HRP owing to its high affinity for TMB. These findings suggest good potential for applications in biosensing and as a catalyst in oxidation reactions. Fe3O4/g-C3N4 nanocomposite efficiently degraded Rhodamine B via Fenton and photo-Fenton reactions, mimicked horseradish peroxidase-like activity for TMB oxidation, and oxidized dopamine showing potential for use in biocatalysis.