Hollow TiO2/g-C3N4 nanocomposite for photodegradation of volatile organic carbons under visible-light

Abstract

Hollow TiO2/g-C3N4 nanocomposite was prepared using solvothermal method. Two-dimensional g-C3N4 nanosheets were coupled with TiO2 hollow spheres at different ratios to investigate the charge-carrier interactions with the aim of enhancing the photocatalytic properties of the nanocomposite. This coupling was systematically examined by scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, photoluminescence, X-ray photoelectron spectroscopy, and UV diffuse reflectance spectroscopy. The prepared nanocomposite was used for the photodegradation of the volatile organic carbons methyl tetra-butyl ether and toluene present in aqueous solution. Elemental analysis and X-ray diffraction revealed a high-purity sample, while the UV diffuse reflectance spectroscopy demonstrated the presence of a well-defined anatase crystal phase for the TiO2 hollow sphere; and the photoluminescence measurements showed an enhancement in visible-light absorbance, with a good reduction in the electron-hole recombination rate. The performance of the nanocomposites in the photocatalytic degradation of toluene under irradiation with visible-light was evaluated. The 20/80% TiO2/g-C3N4 nanocomposite materials showed highest photocatalytic activity for toluene and methyl tetra-butyl ether, achieving a degradation of more than 90%; this is attributed to the interaction between the two surfaces in the TiO2/g-C3N4 nanocomposite, resulting in a higher performance than the individual components.