N-Loaded TiO2 for Photocatalytic Degradation of Methyl Orange under Visible Light Irradiation

Nitrogen-loaded TiO2(N-loaded TiO2), a visible-light driven catalyst, was successfully synthesized by the modified sol-gel method. Physical characterizations of the as-prepared catalysts have been performed by using X-ray diffraction (XRD), Diffuse reflectance UVvisspectroscopy(DRUVvis), Raman spectroscopyand BETspecific surface areain order to obtain structure-activity relationship. Results from Raman spectroscopy clearly suggested that N atoms were incorporated into the TiO2crystal lattice as evidenced by the vibrational peak of TiN in TiO2-xNx.DR UVvis results also suggested that the nitrogen dopant might be responsible for narrowing the TiO2band gap energy, thus resulting in a shift towards the visiblelight region. Photocatalytic activity of N-loaded TiO2evaluated through the degradation of methyl orange (MO)under visible light irradiation (l> 400 nm) indicated that all N-loaded photocatalysts exhibited significantly higher activities than the unloaded TiO2and Degussa P25 TiO2. According to the results from DR UV-vis, XRD and BET studies, the enhanced photoactivity observed from N-loaded samples might be due to a decrease in TiO2band gap energy and/or changes in chemical and physical properties of the materials upon loading with nitrogen.

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Photocatalytic Hydrogen Production from Water on Ga, Sn-Doped ZnS under Visible Light Irradiation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.925.200 ◽

2014 ◽

Vol 925 ◽

pp. 200-204

Author(s):

Leny Yuliati ◽

Melody Kimi ◽

Mustaffa Shamsuddin

Keyword(s):

Photocatalytic Activity ◽

Hydrogen Production ◽

Visible Light ◽

Band Gap ◽

Visible Light Irradiation ◽

Absorption Edge ◽

Band Gap Energy ◽

Light Irradiation ◽

Photocatalytic Hydrogen Production ◽

Gap Energy

Zinc sulfide (ZnS) has been reported to act as a photocatalyts to reduce water to hydrogen. However, ZnS could not work under visible light irradiation due to its large band gap energy. In order to improve the performance of ZnS, Ga and Sn were doped to ZnS. The series of Ga (0.1),Sn (x)-ZnS with various amounts of Sn (x) was prepared by hydrothermal method. XRD patterns suggested that the addition of Ga might reduce the crystallinity of ZnS, suggesting that Ga might inhibit the crystal growth or agglomeration of ZnS. On the other hand addition of Sn did not much affect the structure of the Ga (0.1)-ZnS. The DR UU-visible spectra confirmed the red shift of the absorption edge with the addition of Ga due to the reduced band gap energy, while the addition of Sn did not much shift the absorption edge of the Ga (0.1)-ZnS to longer wavelength. FESEM images showed that all the prepared samples have sphere-shaped particles and no remarkable change was observed with the addition of Ga or Sn. The photocatalytic hydrogen production from water was carried out at room temperature in the presence of sacrificial agent under visible light irradiation. While ZnS did not show activity under visible light, all the prepared Ga (0.1)-ZnS and Ga (0.1),Sn (x)-ZnS samples exhibited photocatalytic activity for hydrogen production. The highest hydrogen production was achieved on Ga (0.1),Sn (0.01)-ZnS, which activity was ca. three times higher than that of the single doped Ga (0.1)-ZnS. This study clearly showed that Sn acted as a good co-dopant to increase the photocatalytic activity of Ga (0.1)-ZnS for hydrogen production from water under visible light irradiation.

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Facile synthesis of AC@TiO2-S with improved visible light photocatalytic activity and recyclability through a controllable sol–gel approach

RSC Advances ◽

10.1039/c5ra07020a ◽

2015 ◽

Vol 5 (70) ◽

pp. 56808-56814 ◽

Cited By ~ 2

Author(s):

Zhiying Duan ◽

Zhichao Wang ◽

Chufeng Sun ◽

Lianbiao Zhao ◽

Yanbin Wang

Keyword(s):

Photocatalytic Activity ◽

Methyl Orange ◽

Visible Light ◽

Visible Light Irradiation ◽

Sol Gel ◽

Light Irradiation ◽

Facile Synthesis ◽

Visible Light Photocatalytic Activity ◽

Degradation Of Methyl Orange ◽

Visible Light Photocatalytic

AC@TiO2-S prepared by controlled sol–gel approach exhibits improved photocatalytic activity over AC@TiO2-G prepared by sol–gel approach for the degradation of methyl orange under visible light irradiation and has excellent recyclability.

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Band-gap-energy-adjustable and noble-metal-free modified NiS-Zn Cd1-S for highly efficient visible-light-driven Cr6+ photoreduction in alkaline wastewater

Journal of Physics and Chemistry of Solids ◽

10.1016/j.jpcs.2020.109893 ◽

2021 ◽

Vol 150 ◽

pp. 109893

Author(s):

Linjuan Wang ◽

Ling Zan

Keyword(s):

Visible Light ◽

Band Gap ◽

Noble Metal ◽

Band Gap Energy ◽

Gap Energy ◽

Metal Free ◽

Highly Efficient ◽

Visible Light Driven

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Photocatalytic Performance of SnO2:Mo Nanopowders Against the Degradation of Methyl Orange and Rhodamine B Dyes Under Visible Light Irradiation

Journal of Electronic Materials ◽

10.1007/s11664-018-6720-9 ◽

2018 ◽

Vol 48 (1) ◽

pp. 401-408 ◽

Cited By ~ 9

Author(s):

N. Manjula ◽

G. Selvan ◽

A. R. Balu

Keyword(s):

Methyl Orange ◽

Visible Light ◽

Visible Light Irradiation ◽

Rhodamine B ◽

Photocatalytic Performance ◽

Light Irradiation ◽

Degradation Of Methyl Orange

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Effect of ZnO on a Superhydrophilic Self-Cleaning Properties of TiO2/SiO2 Thin Film on Glass Slide Substrate

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1131.237 ◽

2015 ◽

Vol 1131 ◽

pp. 237-241 ◽

Cited By ~ 1

Author(s):

Akkarat Wongkaew ◽

Chanida Soontornkallapaki ◽

Naritsara Amhae ◽

Wichet Lamai

Keyword(s):

Thin Film ◽

Contact Angle ◽

Visible Light ◽

Band Gap ◽

Sol Gel ◽

Dip Coating ◽

Band Gap Energy ◽

Gap Energy ◽

Coating Method ◽

Dip Coating Method

This work aims to study the effect of ZnO containing in TiO2/SiO2 film on the superhydrophilic property after exposed to different types of light. The metal solutions were prepared by sol-gel technique and the film was deposited on glass slides by dip coating method. The parameter studied was the amount of ZnO in the TiO2/SiO2 film. The contents of ZnO were 5-20% weight (increased by 5%). The amount of TiO2 was constant at 30% weight. The obtained films were analyzed for their roughness. The results indicated that film roughness changed according to the ZnO contents. With 5%ZnO in the thin film, the roughness was 0.726 nm while 20%ZnO obtained the roughness of 2.128 nm. UV-Vis spectrophotometer was used for measuring of transmittance of films. At wavelength of 550 nm, the transmittances of each film were greater than 90%. Band gap energy of each film was calculated from the transmittance data. It was found that the average band gap energy of the films was 2.47 eV. Then, the films contained various amount of ZnO were grouped into 2 sets. The first set was exposed to visible light while the other set was exposed to UV. The duration of exposure was 5 hr. Both sets of films after exposed to any light were kept in a black box controlled relative humidity of 85%. Each film was measured contact angle every day. It was found that the 30%TiO2/5%Zn/SiO2 film exposed to visible light showed the best superhydrophilic property. The contact angle was about 0-5° within 3 days. This may due to the reduction of band gap energy in the presence of ZnO in TiO2/SiO2 films to 2.41 eV and the roughness of the film.

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