Photocatalytic Activity of Solar-Light-Active N-Doped TiO2 by Sol-Gel Combustion Method

The present work was dedicated to the tailored synthesis of TiO2nanopowders doped with nitrogen (called TiO2−xNx) for the photocatalytic degradation of methyl orange. In particular, the systems were synthesized by a sol-gel combustion route starting from nitric acid and tetrabutyl titanate (Ti (OC4H9)4) as raw materials. The powders were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), suggesting that anatase phase is obtained at pH value of 4-6 and the heat-treated temperatures as low as 425°C. The photocatalytic activities of the N-doped TiO2nanopowders were monitored from the results of the degradation rate of methyl orange (MO) under solar light irradiation. The dependence of dye degradation rate on photocatalyst amount and initial pH was investigated. Under solar light irradiation, the TiO2doped with 30% N exhibited the highest photocatalytic reactivity, which could be attributed to the structure of the combustion-synthesized catalyst and the change of the bandgap induced by nitrogen inclusion.

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Photodegradation of Metribuzin by Simulated Solar Light Irradiation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.518-523.436 ◽

2012 ◽

Vol 518-523 ◽

pp. 436-439 ◽

Cited By ~ 2

Author(s):

Hui Liu ◽

Le Guan

Keyword(s):

Aqueous Solution ◽

Organic Matter ◽

Degradation Rate ◽

Ph Value ◽

Degradation Process ◽

Potential Ecological Risk ◽

Light Irradiation ◽

Solar Light ◽

Simulated Solar Light ◽

Solar Light Irradiation

Photolysis is expected to be a major degradation process for pollutants in surface water. This paper studied the photodegradation of metribuzin, a widely used herbicide, in aqueous solution under simulated solar light irradiation. Photolysis of metribuzin was enhanced by the higher light intensity, and the major products were deaminometribuzin and nitrite ions. Metribuzin degradation was inhibited in the absence of oxygen and at higher pH value. In addition, iron in water promoted the degradation of metribuzin, while dissolved organic matter lowered the degradation rate. This investigation is helpful for better understanding the transformation and the potential ecological risk of metribuzin in natural water.

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Photocatalytic Degradation of Methylene Blue by NiO Thin Films under Solar Light Irradiation

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.56.152 ◽

2019 ◽

Vol 56 ◽

pp. 152-157 ◽

Cited By ~ 5

Author(s):

Abdelouahab Noua ◽

Hichem Farh ◽

Rebai Guemini ◽

Oussama Zaoui ◽

Tarek Diab Ounis ◽

...

Keyword(s):

Thin Films ◽

Methylene Blue ◽

Photocatalytic Activity ◽

Sol Gel ◽

Visible Region ◽

Optical Transmittance ◽

Dip Coating ◽

Light Irradiation ◽

Solar Light ◽

Solar Light Irradiation

Nickel oxide (NiO) thin films were successfully deposited by sol-gel dip-coating method on glass substrates. The structural, morphological and optical properties in addition to the photocatalytic activity of the prepared films were investigated. The results show that the films have a polycrystalline NiO cubic structure with dense NiO grains and average optical transmittance in the visible region. The photocatalytic properties of the films were studied through the degradation of methylene blue and 89% of degradation was achieved for 4.5h of solar light irradiation exposure which indicates the capability of NiO photocatalytic activity.

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Nonmetal–metal–semiconductor-promoted P/Ag/Ag2O/Ag3PO4/TiO2 photocatalyst with superior photocatalytic activity and stability

Journal of Materials Chemistry A ◽

10.1039/c5ta05153c ◽

2015 ◽

Vol 3 (34) ◽

pp. 17858-17865 ◽

Cited By ~ 59

Author(s):

Xiaohong Hu ◽

Qi Zhu ◽

Xinlong Wang ◽

Naoki Kawazoe ◽

Yingnan Yang

Keyword(s):

Photocatalytic Activity ◽

Sol Gel ◽

Light Irradiation ◽

Solar Light ◽

Tio2 Photocatalyst ◽

Photocatalytic Ability ◽

Composite Photocatalyst ◽

Gel Method ◽

Simulated Solar Light ◽

Solar Light Irradiation

P/Ag/Ag2O/Ag3PO4/TiO2 composite photocatalyst has been successfully prepared by a sol–gel method. It shows highly enhanced photocatalytic ability and stability under simulated solar light irradiation.

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Thickness Effect of Zno Film on the Performance of Photocatalytic in a p-Nio/n-Zno Heterostructure under Solar Light Irradiation

Journal of Nano Research ◽

10.4028/www.scientific.net/jnanor.62.87 ◽

2020 ◽

Vol 62 ◽

pp. 87-95

Author(s):

Hichem Farh ◽

Abdelouahab Noua ◽

Rebai Guemini ◽

Djamal Eldine Guitoume ◽

Oussama Zaoui

Keyword(s):

Methylene Blue ◽

Photocatalytic Activity ◽

Degradation Rate ◽

Visible Region ◽

Light Irradiation ◽

Thickness Effect ◽

Solar Light ◽

Zno Films ◽

Zno Film ◽

Solar Light Irradiation

In this work, we studied the ZnO film thickness effect on the photocatalytic performance of n-ZnO/p-NiO heterostructures. The ZnO and NiO films were prepared by sol-gel dip-coating technique and the thickness of the ZnO film was varied by changing the number of coatingsfrom 2 to12. The formation of the p-NiO/n-ZnO heterostructure was confirmed by X ray diffraction (XRD). The obtained ZnO films present a wurtzite structure with a preferred orientation along (002) direction while the NiO film present a cubic structure highly oriented along (200) direction. UV-visible transmittance spectra of the prepared heterostructures revealed a good transparency in the visible region. The photocatalytic propertiesof the n-ZnO/p-NiO heterostructures were investigated by measuring the degradation rate of methylene blue. All the samples exhibit a good photocatalytic activity under solar light irradiation. The photocatalytic activity of p-NiO/n-ZnO heterostructureswas strongly correlated with the number of ZnO coatings. The highest photocatalytic activity was obtained at 6 coatings with a degradation rate of methylene blue equal to 98.67% for 4.5h of irradiation.

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SmFeTaO Photocatalyst for Degradation of Indigo Carmine Dye under Solar Light Irradiation

International Journal of Photoenergy ◽

10.1155/2012/939608 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

Leticia M. Torres-Martínez ◽

Miguel A. Ruiz-Gómez ◽

M. Z. Figueroa-Torres ◽

Isaías Juárez-Ramírez ◽

Edgar Moctezuma

Keyword(s):

Solid State ◽

Sol Gel ◽

Indigo Carmine ◽

Light Irradiation ◽

Solar Light ◽

Recombination Rates ◽

Monoclinic Crystal ◽

Conventional Solid State Reaction ◽

Solar Light Irradiation ◽

Indigo Carmine Dye

This paper is focused to study Sm2FeTaO7pyrochlore-type compound as solar photocatalyst for the degradation of indigo carmine dye in aqueous solution. Sm2FeTaO7was synthesized by using conventional solid state reaction and sol-gel method. X-ray diffraction results indicated that Sm2FeTaO7exhibit a monoclinic crystal structure. By scanning electron microscopy analysis, it was observed that sol-gel material presents particle size of around 150 nm. The specific surface area and energy bandgap values were 12 m2 g−1and 2.0 eV, respectively. The photocatalytic results showed that indigo carmine molecule can be degraded under solar light irradiation using the synthesized materials, sol-gel photocatalyst was 8 times more active than solid state. On the other hand, when Sm2FeTaO7was impregnated with CuO as cocatalyst the photocatalytic activity was increased because CuO acts as electron trap decreasing electron-hole pair recombination rates.

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CuO@TiO2 and NiO@TiO2 core-shell catalysts for hydrogen production from the photocatalytic reforming of glycerol aqueous solution

Journal of Applied Research and Technology ◽

10.22201/icat.24486736e.2020.18.6.1365 ◽

2020 ◽

Vol 18 (6) ◽

pp. 390-409

Author(s):

S. P. Ramírez ◽

J. A. Wang ◽

M. A. Valenzuela ◽

L. F. Chen ◽

A. Dalai

Keyword(s):

Electron Microscopy ◽

Aqueous Solution ◽

Hydrogen Production ◽

Diffuse Reflectance Spectroscopy ◽

Sol Gel ◽

Light Irradiation ◽

Solar Light ◽

Core Shell ◽

Tio2 Catalyst ◽

Solar Light Irradiation

Hydrogen production from the photocatalytic reforming of glycerol aqueous solution was performed on the CuO@TiO2, NiO@TiO2, NiO@CuO, and CuO@NiO core-shell nanostructured catalysts under simulated solar light irradiation. These catalysts were prepared by the combination of a modified sol-gel and a precipitation-deposition method using hydroxypropyl cellulose as structural linker and they were characterized by powder X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (UV–Vis DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen physisorption isotherms techniques. The catalysts containing TiO2 as a shell and CuO as core showed much higher activity compared with those formulated with NiO@CuO, CuO@NiO, and bared CuO or NiO nanoparticles. The highest rate of hydrogen production obtained with the CuO@TiO2 catalyst was as high as 153.8 μmol·g−1h-1, which was 29.0, 24.8, 11.2 and 3.2 times greater than that obtained on CuO@NiO, NiO@CuO, TiO2 P25, and NiO@TiO2 catalyst, respectively. For the high active CuO@TiO2 catalyst, after activation of TiO2 with solar light irradiation, the conduction band electrons can be transferred to CuO core through the heterojunction in the core-shell interfaces which led to CuO gradually reduced to Cu2O, favoring the reduction of proton to release hydrogen.

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