A facile synthesis of g-C3N4/BaTiO3 photocatalyst with enhanced activity for degradation of methylene blue under visible light

g-C3N4/BaTiO3 composite was hydrothermally synthesized at 200 degrees C for 24 h from a dispersed mixture of g-C3N4 and BaTiO3 in water, in which BaTiO3 was hydrothermally synthesized at 200 degrees C for 48 h using barium nitrate, isopropanol, titanium tetrachloride and sodium hydroxide as precursors without assistance of any surfactant; and graphitic carbon nitride (g-C3N4) was prepared by pyrolysis of melamine at 520 degrees C. The obtained materials were characterized by X-ray diffraction, infrared spectra, scanning electron microscopy, elemental mapping, X-ray photoelectron spectroscopy and ultraviolet-visible diffuse reflectance spectroscopy. The photocatalytic activity of the materials was assessed by degradation of methylene blue (MB) under visible light. The enhancement of photocatalytic activity of the g-C3N4/BaTiO3 composite compared to the single components, g-C3N4 and BaTiO3 was observed, which is attributed to the reduction of combination rate of photogenerated electron-hole pairs in the composite. The MB degradation over the composite was mainly attributed to the photoreduction process induced by the superoxide radical anions (O-center dot(2)-) and hydroxyl radicals ((OH)-O-center dot); and a mechanism was also proposed based on the heterojunction model from the two semiconductor components.

Automated summary

In this study, a g-C3N4/BaTiO3 composite was prepared and characterized, showing enhanced photocatalytic activity compared to the individual components. The improvement was attributed to the reduced combination rate of photogenerated electron-hole pairs in the composite, leading to higher catalytic performance.