Designing of TiO2/α-Fe2O3 coupled g-C3N4 magnetic heterostructure composite for efficient Z-scheme photo-degradation process under visible light exposures

Abstract

A novel ternary g-C3N4 coupling with TiO2 and α-Fe2O3 composed magnetic nanocomposite was fabricated by facile calcination and hydrothermal process. The chemical, surface and magnetic characterizations of as-obtained g-C3N4/TiO2/α-Fe2O3 magnetic nanocomposite was explored by various analytical systems. The superior degradation efficiency of magnetic g-C3N4/TiO2/α-Fe2O3 ternary nanocomposite is about 95.7% of Rhodamine B (RhB) in 50 min under visible-light exposure. The photocatalytic upgrading performance was recognized to the synergetic interface among TiO2, g-C3N4 and α-Fe2O3, with effective separation of electron/hole (e-/h+) pair’s, increases in the redox species and great visible-light exploitation owing to less bandgap. The scavenging species presented in superoxide (.O2-) radicals and photo-holes (h+) were played a substantial part and hence establish the Z-scheme RhB dye photo-degradation mechanism. The magnetic g-C3N4/TiO2/α-Fe2O3 ternary PCs still maintain the excellent photo-degradation rate (95.7–88.4%) for the RhB dye aqueous solution after five consecutive recycles, which signifies that the great photocatalyst durability, and is more beneficial for wastewater treatment.