Study On The Assembly And Photocatalytic Application Of Titanoniobate Nanosheets With Metallic Oxide

Photocatalytic degrading organic pollution has many advantages, such as nontoxicity and convenient post-treatment. The titanate, niobate and titanoniobate own layered structure, and can be excited to generate photo-induced electron and hole under visible light by modifying methods. It takes full advantage of the visible light in solar light.The precursor KTiNbO5 was prepared by high temperature solid-state reaction method. After acid exchange and exfoliation-recombination reaction, the corresponding nanosheet (e-HTiNbO5) was obtained successfully. The catalytic activities of as-prepared catalysts were tested by the adsorption and oxidation of ethyl mercaptan. The reaction was carried under solar light irradiation. In present research, we discussed the influence of the speed of adding acid and other factors in the process of exfoliation-recombination reaction. According to the different properties of metallic oxide MOx (M=Zn, Ce), we choose diverse ways to composite the photocatalysts MOx/e-HTiNbO5. The paper adopted many characterization methods to analyst and test the prepared samples. The phase structure was characterized by X-ray powder diffraction (XRD), the morphology was characterized by scanning electron microscope (SEM) or transmission electron microscopy (TEM) and the skeleton structure was characterized by laser Raman spectra(Raman). After Photocatalytic oxidation desulfurization of EM, there are some retention species obtained on the samples, and the species were tested by a Fourier transformed infrared (FT-IR).The results show that lamellar nanosheet will be formed after the process of ion exchange and exfoliation-recombination procedure through the precursor. A good appearance of lamellar nanosheet will be gained by controlling the adding speed of the HNO3. The corresponding material obtained by nanosheet-restocking keeps a typical layered structure with different degree of crystallinity. The nanocomposite MOx/e-HTiNb05 has good photocatalytic oxidation activity in the experiment of photocatalytic oxidation desulfurization of ethanethiol (EM). An obvious interaction existed between MOx and e-HTiNbO5 nanosheet, and it causes a lower bandgap energy. The photocatalytic oxidation activity of nanocomposite has effectively been enhanced, the electron-hole pairs can be separated effectively.The results show that the nanocomposite MOx/e-HTiNb05 (M=M=Zn, Ce) have good photocatalytic oxidation activity to organic sulfur. The modification of nanosheet can not only increase the specific surface area, but also boost the adsorption ability effectively. In conclusion, the nanocomposite MOx/e-HTiNbO5 has good catalytic activity to organic sulfur, and this provides a green way for organic sulfur removal.