Preparation and Physical and Photocatalytic Activity of a New Niobate Oxide Material Containing NbO₄ Tetrahedra

Abstract

The shape and connection type of MOx are critical to the physical and chemical properties. A series of new material Sr2-xNaxNbO4 containing NbO4 tetrahedra was prepared by controlling the ratio of SrCO3 to sodium niobate under ambient air. With increasing the content of Sr in the sample, the MOx shape will change from NbO6 octahedra to NbO4 tetrahedra, which is confirmed by the Raman scattering spectra. With increasing the content of NbO4 in the sample, the lattice parameter increases, optical band gap becomes larger, and the surface changes to be more active for oxygen adsorption, resulting in a higher photocatalytic activity.

Fast synthesis of NaNbO3 nanoparticles with high photocatalytic activity for degradation of organic dyes

“…However, the sample treated at 600°C has a band gap of 3.45 eV. This band gap reduction in the material is a consequence of the reduction of the lattice distance that generates a greater expansion of the energy level 54 . Therefore, the sample treated at 600°C has a slightly smaller band gap because it has smaller cell parameters, as shown by the deviations of diffraction peaks for larger angles, shown in Figure 1.…”

“…This band gap reduction in the material is a consequence of the reduction of the lattice distance that generates a greater expansion of the energy level. 54 Therefore, the sample treated at 600 • C has a slightly smaller band gap because it has smaller cell parameters, as shown by the deviations of diffraction peaks for larger angles, shown in Figure 1. The reduction in bandgap favors photocatalysis, as the semiconductor requires less energy to activate.…”