N, Fe and WO3 modified TiO2 for degradation of formaldehyde

Butyltitanate, ethanol and glacial acetic acid were chosen as titanium source, solvent and chelating agent, respectively, via a sol–gel method combined impregnation method to prepare N, Fe co-doped and WO3 compounded photocatalyst TiO2 powder. The synthesized products were characterized by X-ray diffraction (XRD), diffuse reflectance UV–Vis spectra (UV-DRS), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Photocatalytic degradation of formaldehyde was employed to investigate the catalytic activity. The results show that the degradation rate is 77.61% in 180 min under UV light irradiation when the concentration of N is fixed on, and the optimum proportioning ratio of n(Fe):n(W):n(Ti) is 0.5:2:100.

The undoped TiO2 powder (T(0)) shows strong photoabsorption only at wavelengths shorter than 400 nm, and while Fe3+ and N-doped TiO2 nanoparticles show photoabsorption in visible region and the absorption edge shifts to a longer wavelength. WO3 compounding also benefits the photoabsorption in visible region.Figure optionsDownload as PowerPoint slideHighlights
► The preparation of the catalysts co-doped by Fe, N and compounded by WO3.
► The obvious sculptured “pattern” of the catalysts doped by Fe in the SEM images.
► Strengthened photoabsorption to visible light of the modified catalysts from UV-DRS analysis.