Visible-Light Active Sulfur-Doped Titania Nanoparticles Immobilized on a Silica Matrix: Synthesis, Characterization and Photocatalytic Degradation of Pollutants

The photocatalytic oxidation (PCO) of pollutants using TiO2-based materials can significantly improve indoor air quality (IAQ), which in turn, has a significant impact on human health and life expectancy. TiO2-based nanoparticles (NPs) are widely used as part of building materials to function as photocatalysts in PCO. In this work, a series of sulfur-doped TiO2 NPs immobilized on a silica matrix were synthesized by combining a sol-gel process with ball milling. The samples were structurally characterized by X-ray diffraction (XRD), UV-Vis diffuse reflectance spectroscopy (DRS), Fourier-transform infrared spectroscopy (FT-IR) and N2 adsorption-desorption isotherms. Furthermore, the morphological characteristics were determined by dynamic light scattering (DLS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The photocatalytic activity of the as prepared S-doped TiO2/SiO2 NPs in the degradation of liquid and air pollutants under visible-light irradiation was investigated. Our results show that sulfur is an effective dopant for activating TiO2/SiO2 photocatalysts under visible-light irradiation. Silica constitutes a “safe-by-design” approach and inhibits the aggregation of NPs during synthesis. The most efficient photocatalyst afforded 79% removal of methyl orange (5 h), 26% removal of acetaldehyde (1 h) and 12% oxidation of NO (1 h).

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Sterilization of E. Coli by Fe-Doped TiO2 Modified Photocatalytic Paint under Visible Light Irradiation

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1493 ◽

2008 ◽

Vol 368-372 ◽

pp. 1493-1496 ◽

Cited By ~ 1

Author(s):

Rong Liang He ◽

Yi Wei ◽

Wen Bin Cao

Keyword(s):

Visible Light ◽

Visible Light Irradiation ◽

Diffuse Reflectance ◽

Diffuse Reflectance Spectroscopy ◽

Reflectance Spectroscopy ◽

Light Irradiation ◽

Nanocrystalline Powders ◽

Latex Paint ◽

Doped Tio2 ◽

E Coli

Photocatalytic paint was prepared by adding Fe-doped TiO2 nanocrystalline powders into self-engineered oxidation-resistant latex paint system. The UV-Vis diffuse reflectance spectroscopy was used to characterize the light absorption properties of the paint. The colony counting method was used to study photocatalytic sterilization ratio of E. coli under visible light irradiation. Effects of the kinds and amounts of TiO2 powders added in the paint on the sterilization ratio under visible light irradiation with fixed relative humidity were systematically investigated. The UV-Vis diffuse reflectance spectroscopy indicates that the absorption thresholds of the Fe-doped TiO2 paint have red-shifted into visible light region. The antibacterial experiment results show that the sterilization ratio of E. coli can exceed more than 99% in less than 4 hours under 400-lux-visible light irradiation under RH of 55%.

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Design and fabrication of Ag3VO4/g-C3N4 heterostructure photocatalyst for enhanced visible light degradation of various organic pollutants

10.21203/rs.3.rs-329610/v1 ◽

2021 ◽

Author(s):

N Sujatha ◽

M Meenachi ◽

S Mohammed Harshulkhanb ◽

H.H Hegazy

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Visible Light Irradiation ◽

Photoelectron Spectroscopy ◽

Diffuse Reflectance Spectroscopy ◽

Light Irradiation ◽

X Rays ◽

Hydrothermal Route ◽

X Ray ◽

Visible Light Degradation

Abstract In later years, numerous viable photocatalysts have been created in order to illuminate the issues of natural toxins. In this work, heterostructured photocatalysts Ag3VO4/g-C3N4 were prepared by effortless hydrothermal route in order to anchor Ag3VO4 on the surface of the g-C3N4 nanosheets. The prepared samples were fairly characterized using X-ray diffraction (XRD), Energy dispersive analysis of X-rays (EDAX), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), UV-vis diffuse reflectance spectroscopy (UV-DRS), photoluminescence, and X-ray photoelectron spectroscopy (XPS) techniques. The photocatalytic activity of the samples was evaluated by degrading malachite green (MG) and 2,4 dimethyl phenol (DMP) in aqueous solution under visible light irradiation. Compared with Ag3VO4 and g-C3N4, the heterojuncted photocatalyst 50 wt% Ag3VO4/g-C3N4 exhibits the best activity such as high degradation efficiency (99%), high apparent constant (0.0923 min− 1) and long term stability towards DMP under visible light irradiation. The development of a phase scheme heterojunction between Ag3VO4 and g-C3N4 improved the photocatalytic efficiency of Ag3VO4/g-C3N4 composites. Furthermore, the porous structure of g-C3N4 and the effect of Ag surface plasmon resonance (SPR) speed up the isolation and transfer of electron-hole pairs, reducing the likelihood of recombination.

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Photocatalytic Antibacterial Effectiveness of Cu-Doped TiO2 Thin Film Prepared via the Peroxo Sol-Gel Method

Catalysts ◽

10.3390/catal8090352 ◽

2018 ◽

Vol 8 (9) ◽

pp. 352 ◽

Cited By ~ 14

Author(s):

Benjawan Moongraksathum ◽

Jun-Ya Shang ◽

Yu-Wen Chen

Keyword(s):

Electron Microscopy ◽

Methylene Blue ◽

Visible Light ◽

Visible Light Irradiation ◽

Sol Gel ◽

Light Irradiation ◽

Gel Method ◽

Doped Tio2 ◽

X Ray ◽

Photocatalytic Activities

Cu-doped titanium dioxide thin films (Cu/TiO2) were prepared on glass substrate via peroxo sol-gel method and dip-coating process with no subsequent calcination process for the degradation of organic dye and use as an antibacterial agent. The as-prepared materials were characterised using transmission electron microscopy (TEM), X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). For photocatalytic degradation of methylene blue in water, the samples were subjected to Ultraviolet C (UVC) and visible light irradiation. Degraded methylene blue concentration was measured using UV-Vis spectrophotometer. The antibacterial activities of the samples were tested against the gram-negative bacteria Escherichia coli (ATCC25922). Copper species were present in the form of CuO on the surface of modified TiO2 particles, which was confirmed using TEM and XPS. The optimal observed Cu/TiO2 weight ratio of 0.5 represents the highest photocatalytic activities under both UVC and visible light irradiation. Moreover, the same composition remarkably exhibited high antibacterial effectiveness against E. coli after illumination with ultraviolet A. The presence of CuO on TiO2 significantly enhanced photocatalytic activities. Therefore, active Cu-doped TiO2 can be used as a multipurpose coating material.

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Zinc and boron co-doped nanotitania with enhanced photocatalytic degradation of Acid Red 6A under visible light irradiation

Sustainable Environment Research ◽

10.1186/s42834-019-0031-6 ◽

2019 ◽

Vol 29 (1) ◽

Cited By ~ 1

Author(s):

Ravi Kumar Mulpuri ◽

Siva Rao Tirukkovalluri ◽

Manga Raju Imandi ◽

Shaik Abdul Alim ◽

Venkata Divya Lakshmi Kapuganti

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Visible Light Irradiation ◽

Diffuse Reflectance Spectroscopy ◽

Light Irradiation ◽

Reaction Parameters ◽

X Ray ◽

Nano Catalyst ◽

Optimum Reaction ◽

Co Doped

AbstractThe present investigation summarizes the synthesis and characterization of zinc and boron co-doped TiO2 nano catalyst by sol gel method at relatively low temperature and explored the optimum reaction parameters for the degradation of Acid Red 6A (AR 6A) under visible light irradiation. The structural, morphological, surface properties of the synthesized photocatalysts were characterized by X-Ray Diffraction, Scanning Electron Microscopy-Energy Dispersive X-ray Spectroscopy, Transmission Electron Microscopy, Brunauer-Emmett-Teller, UV-Vis-Diffuse Reflectance Spectroscopy, X-ray Photo Electron Spectroscopy and Fourier Transform-Infra Red Spectroscopy. The findings of the characterization results revealed that Zn2+ ion was substitutionally doped into TiO2 lattice by replacing Ti4+ ion and a part of the boron substituted the oxygen in TiO2 lattice and the remaining amount was converted to B2O3 due to calcinations at 450 °C. The degradation of AR 6A was achieved at optimum reaction parameters, such as pH = 6 with a catalyst dosage 100 mg L−1 for the degradation of 5 mg L−1 of dye solution.

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Structure and Photocatalytic Activity of Nitrogen-doped HTiNbO5 Nanosheet Aggregation

NANO ◽

10.1142/s1793292017500035 ◽

2017 ◽

Vol 12 (01) ◽

pp. 1750003 ◽

Cited By ~ 5

Author(s):

Wei Lv ◽

Jie He ◽

Andong Xu ◽

Lifang Hu ◽

Liangguo Da

Keyword(s):

Electron Microscopy ◽

Photocatalytic Activity ◽

Visible Light ◽

Visible Light Irradiation ◽

Diffuse Reflectance Spectroscopy ◽

Proton Exchange ◽

Light Irradiation ◽

Laser Raman Spectroscopy ◽

X Ray ◽

Nitrogen Doped

Nitrogen-doped HTiNbO5 nanosheet (N-HTiNbO5-NS) aggregation was successfully obtained through a series of process, including preparation of nitrogen-doped precursor (N-KTiNbO5), proton-exchange of N-KTiNbO5 and exfoliation of N-HTiNbO5. The structures of the as-prepared samples are characterized by means of powder X-ray diffraction (XRD), Scan electron microscopy (SEM), Transmission electron microscopy (TEM), N2 adsorption-desorption isotherms UV-visible diffuse reflectance spectroscopy (UV-Vis-DRS), Laser Raman spectroscopy (LRS), X-ray photoelectron spectroscopy (XPS) and Thermogravimetric analysis-differential scanning calorimetry (TG-DSC). The catalytic activities of the as-prepared samples are evaluated by the photocatalytic degradation of methylene blue (MB) aqueous solution under visible light irradiation. The results reveal that N-HTiNbO5-NS due to the large specific surface area and brilliant visible light response exhibits a relatively excellent photocatalytic activity in the decomposition of MB under visible light irradiation.

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

Journal of Hazardous Materials ◽

10.1016/j.jhazmat.2011.09.010 ◽

2011 ◽

Vol 196 ◽

pp. 426-430 ◽

Cited By ~ 64

Author(s):

Jie Xu ◽

Wenzhong Wang ◽

Meng Shang ◽

Erping Gao ◽

Zhijie Zhang ◽

...

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Visible Light Irradiation ◽

Electrospun Nanofibers ◽

High Photocatalytic Activity ◽

Light Irradiation ◽

Doped Tio2

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Efficient photocatalytic degradation of phenol by Ag-doped TiO2 nanocomposite photocatalysts under visible light irradiation in a three-phase fluidized bed reactor

Chemical Papers ◽

10.1007/s11696-021-01531-z ◽

2021 ◽

Author(s):

Nasim Yavari ◽

Omid Tavakoli ◽

Mohammad Javad Parnian

Keyword(s):

Visible Light ◽

Photocatalytic Degradation ◽

Fluidized Bed ◽

Visible Light Irradiation ◽

Fluidized Bed Reactor ◽

Light Irradiation ◽

Doped Tio2 ◽

Three Phase

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Photocatalytic Degradation of Methylene Blue over Co-Ag3VO4 under Visible Light Irradiation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.335-336.1385 ◽

2011 ◽

Vol 335-336 ◽

pp. 1385-1390 ◽

Cited By ~ 1

Author(s):

Shuo Wiei Zhao ◽

Hui Xu ◽

Hua Ming Li ◽

Yuan Guo Xu

Keyword(s):

Methylene Blue ◽

Photocatalytic Activity ◽

Visible Light ◽

Visible Light Irradiation ◽

Absorption Edge ◽

Diffuse Reflectance Spectroscopy ◽

Dye Degradation ◽

Light Irradiation ◽

Experimental Conditions ◽

X Ray

In order to improve the photocatalytic activity, Co was successfully loaded into Ag3VO4 by using impregnation process. The samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS) and diffuse reflectance spectroscopy (DRS). The XRD and SEM–EDS analyses revealed that Co ion was dispersed on Ag3VO4. The DRS results indicated that the absorption edge of the Co–Ag3VO4 catalyst shifted to longer wavelength. The enhanced photocatalytic activity of Co–Ag3VO4 for Methylene Blue(MB) dye degradation under visible light irradiation was due to its wider absorption edge and higher separation rate of photo-generated electron and holes. In the experimental conditions, it is demonstrated that the MB was effectively degraded by more than 95% within 40 min when the Co–Ag3VO4 catalyst was calcined at 300°C with 1 wt.% Co content.

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