Abstract:

A novel composite material TiO₂-HNbMoO₆ was prepared by an intercalation-pillar route. The phase and its microstructure, skeleton feature, spectral-response characteristics, and the interaction between interlayer species and nanosheets were characterized using powder X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), laser Raman spectroscopy (LRS), X-ray photoelectron spectroscopy (XPS), UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), and H₂ temperature-programmed reduction (H₂-TPR). The specific surface areas of the samples were measured by N₂ adsorption-desorption isotherms. The synergistic effect between the host and the guest of the composites was evaluated by the degradation of methylene blue (MB) dye under simulated sunlight. The results, such as the increase of the d-spacing, the absence of TiO₂ crystalline phase, and the change of the Nb―O bond in the main body and the Ti―O bond in TiO₂ before and after composition, demonstrate that TiO₂ is uniformly dispersed in the interlayer of HNbMoO₆, indicating the interaction between the host laminates and the guest titanium oxide species. The specific surface area of the composite was four times that of its host material, the narrowing band gap, the better adsorption ability, and the superior photocatalytic activity of TiO₂-HNbMoO₆ were because of the synergistic effect between the host and the guest.

Key words: HNbMoO₆, TiO₂, Composite structure, Photocatalysis, Synergistic effect