Synthesis of α-Fe2O3 decorated g-C3N4/ZnO ternary Z-scheme photocatalyst for degradation of tartrazine dye in aqueous media

Abstract

Abstract In this study, we report the synthesis of a novel α-Fe2O3 decorated g-C3N4/ZnO (g-C3N4/ZnO@α-Fe2O3) ternary Z-scheme photocatalyst for degradation of organic dye. The g-C3N4/ZnO@α-Fe2O3 ternary nanocomposite was synthesized by using the direct pyrolysis and sol-gel methods. Different physicochemical methods were used to confirm the as-synthesized nanomaterials including Transmission electron microscopy, high-resolution field-emission scanning electron microscopy, Fourier Transform infrared spectroscopy, and X-ray photoelectron spectroscopy. The as-synthesized different nanocomposite materials were used to investigate the photodegradation of tartrazine (Acid Yellow 23). Photoluminescence spectra revealed that the g-C3N4/ZnO@α-Fe2O3 ternary nanocomposite has lower recombination rate than pristine g-C3N4. The as-synthesized nanocomposite showed high photocatalytic activity towards degradation of tartrazine than that of g-C3N4, ZnO, ZnO@α-Fe2O3. Also, g-C3N4/ZnO@α-Fe2O3 nanocomposite can able to degrade 99.34% of tartrazine within 35 min under visible light irradiation. The g-C3N4/ZnO@α-Fe2O3 nanocomposite has a higher rate constant and excellent cyclic stability towards the photodegradation of tartrazine. The electrochemical impedance spectra results confirmed that the g-C3N4/ZnO@α-Fe2O3 nanocomposite has faster electron-transfer ability towards the electrode surface than that of g-C3N4, ZnO, and ZnO@α-Fe2O3 composite.