Ultrasound-assisted synthesis and visible-light-driven photocatalytic activity of Fe-incorporated TiO2 nanotube array photocatalysts.

Fe incorporated TiO(2) nanotube arrays (Fe-TiO(2)NTs) were prepared by an ultrasound-assisted impregnating-calcination method. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and UV-vis diffuse reflectance spectroscopy (DRS) indicated that α-Fe(2)O(3) nanoparticles were deposited into the TiO(2) nanotubes, and in the mean time, some Fe(3+) ions were doped into TiO(2) lattice. The absorption of Fe-TiO(2)NTs in the visible light region increased with the increase of Fe content. The photocatalytic activity of Fe-TiO(2)NTs was evaluated by the degradation of methylene blue aqueous solution under visible light irradiation. The results demonstrated that the Fe-TiO(2)NTs exhibited significantly enhanced photocatalytic activity compared with pure TiO(2)NTs. Photoluminescence (PL) and electrochemical impedance spectroscopy (EIS) analyses further confirmed that the increased photocatalytic activity of the Fe-TiO(2)NTs was attributed to an enhanced separation and transfer of photogenerated charge carriers.

Wu Q ，Ouyang J ，Xie K ，Sun L ，Wang M ，Lin C ... -  《-》

Electrospun nanofibers of Bi-doped TiO2 with high photocatalytic activity under visible light irradiation.

Bi-doped TiO(2) nanofibers with different Bi content were firstly prepared by an electrospinning method. The as-prepared nanofibers were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), photoluminescence spectra (PL), and UV-vis diffuse reflectance spectroscopy (DRS). The results indicated that Bi(3+) ions were successfully incorporated into TiO(2) and extended the absorption of TiO(2) into visible light region. The photocatalytic experiments showed that Bi-doped TiO(2) nanofibers exhibited higher activities than sole TiO(2) in the degradation of rhodamine B (RhB) and phenol under visible light irradiation (λ>420 nm), and 3% Bi:TiO(2) samples showed the highest photocatalytic activities.

Xu J ，Wang W ，Shang M ，Gao E ，Zhang Z ，Ren J ... -  《-》

Ultrasound aided photochemical synthesis of Ag loaded TiO2 nanotube arrays to enhance photocatalytic activity.

Sun L ，Li J ，Wang C ，Li S ，Lai Y ，Chen H ，Lin C ... -  《-》

Highly efficient visible light TiO2 photocatalyst prepared by sol-gel method at temperatures lower than 300°C.

Highly efficient visible light TiO(2) photocatalyst was prepared by the sol-gel method at lower temperature (≤ 300°C), and characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier-transform infrared spectroscopy (FTIR), UV-vis diffuse reflectance spectroscopy (UV-vis DRS), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and differential scanning calorimetry-thermogravimetric analysis (DSC-TGA). The effects of the heat treatment temperature and time of the as-prepared TiO(2) on its visible light photocatalytic activity were investigated by monitoring the degradation of methyl orange solution under visible light irradiation (wavelength ≥ 400 nm). Results show that the as-prepared TiO(2) nanoparticles possess an anatase phase and mesoporous structure with carbon self-doping and visible photosensitive organic groups. The visible light photocatalytic activity of the as-prepared TiO(2) is greatly higher than those of the commercial TiO(2) (P-25) and other visible photocatalysts reported in literature (such as PPy/TiO(2), P3HT/TiO(2), PANI/TiO(2), N-TiO(2) and Fe(3+)-TiO(2)) and its photocatalytic stability is excellent. The reasons for improving the visible light photocatalytic activity of the as-prepared TiO(2) can be explained by carbon self-doping and a large amount of visible photosensitive groups existing in the as-prepared TiO(2). The apparent optical thickness (τ(app)), local volumetric rate of photo absorption (LVRPA) and kinetic constant (k(T)) of the photodegradation system were calculated.

Wang D ，Xiao L ，Luo Q ，Li X ，An J ，Duan Y ... -  《-》

Electrospun nanofibers of V-doped TiO2 with high photocatalytic activity.

In this work, V-doped TiO(2) nanofibers with different V contents have been fabricated by an electrospinning technique. The as-prepared nanofibers were characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), Raman spectra, X-ray photoelectron spectroscopy (XPS), and UV-Vis diffuse reflectance (DR) spectroscopy. The results indicated that the V(4+) or V(5+) ions were successfully incorporated into the crystal lattice of anatase TiO(2) nanofibers. Meanwhile, the V doping could extend the visible light absorption of TiO(2) nanofibers. The photocatalytic experiments indicated that the obtained V-doped TiO(2) nanofibers possessed high activity for the photodegradation of organic pollutant methylene blue (MB). Especially, the 1.0 and 5.0 wt.% V-doped TiO(2) nanofibers exhibited the best catalytic activity under visible and ultraviolet (UV) light irradiation, respectively. Also, these nanofibers could be easily recycled without a decrease of the photocatalytic activity.

Zhang Z ，Shao C ，Zhang L ，Li X ，Liu Y ... -  《-》