Photocatalytic activities of g-C3N4, Bi3NbO7 and g-C3N4/Bi3NbO7 in photocatalytic reduction of Cr(Ⅵ)

2013 ◽

Vol 690-693 ◽

pp. 1081-1085

Author(s):

Xue Fei Lei ◽

Xiang Xin Xue ◽

He Yang

Keyword(s):

Photocatalytic Activity ◽

Blast Furnace ◽

Blast Furnace Slag ◽

Preparation Method ◽

Surface Acidity ◽

Visible Region ◽

Photocatalytic Reduction ◽

Dry Process ◽

Photocatalytic Activities ◽

Furnace Slag

The paper investigates the feasibility to reduce Cr (VI) from the aqueous solution by sulfate-modified titanium-bearing blast furnace slag (STBBFS) prepared with the different preparation method. The different photocatalysts were examined by X-ray diffraction (XRD), UV-vis diffuse reflectance spectra and scanning electronic microscopy (SEM). The photocatalytic activities of the different catalysts were evaluated by the photocatalytic reduction of Cr (VI) under UV-vis light irradiation. For the photocatalytic reduction of Cr (VI), the photocatalytic activities of STBBFS catalysts were found to be strongly dependent of absorbance in UV-visible region, adsorption capacity and surface acidity, and STBBFS prepared by dry-process showed a higher photocatalytic activity compared to that prepared by hydro-chemistry method.

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Solid-phase Synthesis of Visible-light-driven BiVO4 Photocatalyst and Photocatalytic Reduction of Aqueous Cr(VI)

BULLETIN OF CHEMICAL REACTION ENGINEERING AND CATALYSIS ◽

10.9767/bcrec.14.2.3182.336-344 ◽

2019 ◽

Vol 14 (2) ◽

pp. 336 ◽

Cited By ~ 1

Author(s):

Jing Li ◽

Yan Chen ◽

Chengru Chen ◽

Shaorong Wang

Keyword(s):

Visible Light ◽

Solid Phase ◽

Removal Rate ◽

Photocatalytic Reduction ◽

Diffraction Field ◽

X Ray Diffraction ◽

Phase Synthesis ◽

Photogenerated Electrons ◽

Photocatalytic Activities ◽

Visible Light Driven

This communication reports a pioneering study on the synthesis of BiVO4 and photocatalytic reduction of Cr(VI)-polluted wastewaters. Monoclinic phase BiVO4 micron-crystals with adjustable morphology were synthesized via a solid-phase route. The structures, morphology, optical properties of the BiVO4 micron-crystals were characterized by X-ray diffraction, field emission scanning electron microscopy, UV-vis diffuse reflectance spectra, Fourier transform infrared spectroscopy spectra, and photocurrent measurements. Besides, their photocatalytic properties were tested for the reduction of aqueous Cr(VI) under visible light (l > 420 nm) irradiation. The photocatalytic tests showed that the photocatalytic activities of BiVO4 powders in aqueous Cr(VI) depended on the dark adsorption amount for Cr(VI) and number of photogenerated carriers. BiVO4-(c) exhibited the highest photocatalytic reduction efficiency that attributed to highest separation and transfer efficiency of photogenerated electrons and holes. Besides, effects of photocatalytic experiment parameters (including dosage of photocatalyst and coexistent anions and cations) on the Cr(VI) removal rate by BiVO4-(c) were also investigated, and •OH play an important role in the BiVO4 photocatalytic reduction Cr(VI). Copyright © 2019 BCREC Group. All rights reserved

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Sensitization of TiO2 by the symmetric cationic polymethine dye for the photocatalytic reduction of methylene blue

Functional Materials Letters ◽

10.1142/s1793604719500383 ◽

2019 ◽

Vol 12 (03) ◽

pp. 1950038 ◽

Cited By ~ 1

Author(s):

I. M. Kobasa ◽

I. V. Kondratyeva ◽

Yu. V. Kropelnytska

Keyword(s):

Methylene Blue ◽

Photocatalytic Reduction ◽

Energy Transformation ◽

Test Reaction ◽

Adsorption Band ◽

Light Quanta ◽

Type D ◽

Near Ir ◽

Photocatalytic Activities ◽

Polymethine Dye

Using the spectral, electrochemical and energy transformation characteristics of the cationic polymethine dye (D) 2-[(1E)-1,3-butadienyl-]-1-(phenylmethyl)-benindolium borfluoride, it has been found that the dye can be applied as a highly efficient sensitizer of TiO2. An intensity of the initially narrow light adsorption band becomes wider and embraces practically entire visible and near IR zones as a result of application of the dye to the surface of TiO2. Due to this effect, a wider array of light quanta can potentially be involved in the photocatalytic transformations. Some new heterostructures (HS) of the type D/TiO2 have been developed and their photocatalytic activities were determined in the test reaction of reduction of methylene blue by formaldehyde for different dye contents and under various modes of irradiation. The schemes of the energy transformation initiated by the light with different wavelengths are proposed and discussed.

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Synthesis of ZnO/ZnFe2O4 nanocomposites in organic-free media and their photocatalytic activity under natural sunlight

JOURNAL OF MECHANICAL ENGINEERING AND SCIENCES ◽

10.15282/jmes.14.2.2020.20.0532 ◽

2020 ◽

Vol 14 (2) ◽

pp. 6801-6810

Author(s):

Rahmayeni Rahmayeni ◽

Zulhadjri Zulhadjri ◽

Yeni Stiadi ◽

Agusnar Harry ◽

Syukri Arief

Keyword(s):

Electron Microscopy ◽

Hexagonal Wurtzite Structure ◽

Rice Grain ◽

X Ray Diffraction ◽

Homogeneous Sphere ◽

Natural Sunlight ◽

Transmission Electron ◽

Photocatalytic Activities ◽

Free Media ◽

Photocatalytic Applications

Nanocomposite ZnO/ZnFe2O4 photocatalysts with different proportions of ZnFe2O4 were synthesized in organic-free media using metal nitric as precursors. The ZnO phase with hexagonal wurtzite structure and low crystallinity of ZnFe2O4 was confirmed using XRD (X-Ray diffraction). Different morphologies of the nanocomposites were obtained ranging from rice grain-like with a porous surface to homogeneous sphere-like nanoparticles as shown in Scanning Electron Microscopy (SEM) and TEM Transmission Electron Microscopy (TEM) studies. Magnetic properties measured by Visible Sampler Magnetometer (VSM) showed diamagnetic and paramagnetic behavior for the nanocomposites. Analysis with Diffuse Reflectance Spectrophotometer (DRS) UV-vis showed an increase the composition of ferrite in composites increasing its ability to absorb visible light. Photocatalytic activities of ZnO/ZnFe2O4 nanocomposites on the degradation of Rhodamine B dye reached 95.6% after 3 h under natural sunlight suggesting their suitability for sunlight driven photocatalytic applications.

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