Mesoporous cerium oxide nanospheres for the visible-light driven photocatalytic degradation of dyes

A facile, solvothermal synthesis of mesoporous cerium oxide nanospheres is reported for the purpose of the photocatalytic degradation of organic dyes and future applications in sustainable energy research. The earth-abundant, relatively affordable, mixed valence cerium oxide sample, which consists of predominantly Ce7O12, has been characterized by powder X-ray diffraction, X-ray photoelectron and UV–vis spectroscopy, and transmission electron microscopy. Together with N2 sorption experiments, the data confirms that the new cerium oxide material is mesoporous and absorbs visible light. The photocatalytic degradation of rhodamin B is investigated with a series of radical scavengers, suggesting that the mechanism of photocatalytic activity under visible-light irradiation involves predominantly hydroxyl radicals as the active species.

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Surfactant-Free Microwave-Assisted Synthesis of Fe-Doped ZnO Nanostars as Photocatalyst for Degradation of Tropaeolin O in Water under Visible Light

Journal of Nanomaterials ◽

10.1155/2015/190747 ◽

2015 ◽

Vol 2015 ◽

pp. 1-9 ◽

Cited By ~ 7

Author(s):

Tsz-Lung Kwong ◽

Ka-Fu Yung

Keyword(s):

Visible Light ◽

Photocatalytic Degradation ◽

Irradiation Time ◽

Catalyst Loading ◽

Orthogonal Experimental Design ◽

Microwave Assisted Synthesis ◽

X Ray ◽

Microwave Assisted ◽

Vis Spectroscopy ◽

Doped Zno

Iron-doped zinc oxide nanostar was synthesized by the microwave-assisted surfactant-free hydrolysis method. The as-synthesized Fe-doped ZnO nanostars catalyst was fully characterized by scanning electron microscope (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), powder X-ray diffraction (XRD), and diffuse reflectance UV-vis spectroscopy (UV-DRA). The photocatalytic activity of the photocatalyst was investigated for the photocatalytic degradation of Tropaeolin O under visible light irradiation. It is observed that the doping of Fe ions enhances the absorption of the visible light and thus the photocatalytic degradation rate of Tropaeolin O would increase. Despite the Taguchi orthogonal experimental design method, the photocatalytic conversion could be achieved at 99.8% in the Fe-doped ZnO catalyzed photodegradation reaction under the optimal reaction conditions of catalyst loading (30 mg), temperature (60°C), light distance (0 cm), initial pH (pH = 9), and irradiation time (3 h). The Fe-doped ZnO photocatalyst can also be easily recovered and directly reused for eight cycles with over 70% conversion.

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Visible Light Induced Photocatalytic Degradation of Methyl Red with Codoped Titania

Journal of Catalysts ◽

10.1155/2014/962419 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Susmitha Thota ◽

Siva Rao Tirukkovalluri ◽

Sreedhar Bojja

Keyword(s):

Visible Light ◽

Photocatalytic Degradation ◽

Anatase Phase ◽

Sol Gel ◽

Visible Region ◽

Oxygen Demand ◽

Analytical Techniques ◽

Active Species ◽

Methyl Red ◽

X Ray

Photocatalysis using semiconductor oxides was being investigated extensively for the degradation of dyes in effluent water. This paper reports our findings on visible light induced photocatalytic degradation of azo dye, methyl red mediated nitrogen and manganese codoped nano-titanium dioxide (N/Mn-TiO2). The codoped samples with varying weight percentages were synthesized by sol-gel method and characterized by various analytical techniques. The X-ray diffraction data showed that the synthesized samples were in anatase phase with 2θ at 25.3°. UV-visible diffuse reflectance spectral analysis revealed that the presence of dopants in TiO2 caused a significant absorption shift towards visible region and their presence was confirmed by X-ray photoelectron spectral data. The release of hydroxyl radical (major active species in photocatalytic degradation) by the photocatalyst in aqueous solution under visible light irradiation was quantitatively investigated by the photoluminiscent technique (PL). The effect of various experimental parameters like dopant concentration, pH, catalyst dosage, and initial dye concentrations was investigated and optimum conditions were established. The extent of mineralization of methyl red was studied by chemical oxygen demand (COD) assays and the results showed complete mineralization of the dye.

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Photocatalytic Degradation of Organic Dyes Using ZnO/CeO2 Nanocomposite Material under Visible Light

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.584.381 ◽

2012 ◽

Vol 584 ◽

pp. 381-385 ◽

Cited By ~ 19

Author(s):

R. Saravanan ◽

N. Karthikeyan ◽

S. Govindan ◽

V. Narayanan ◽

A. Stephen

Keyword(s):

Visible Light ◽

Photocatalytic Degradation ◽

Organic Dyes ◽

Decomposition Temperature ◽

Morphological Properties ◽

Synthesis Process ◽

X Ray Diffraction ◽

X Ray ◽

Thermal Decomposition Method ◽

Bet Method

Nanorods of ZnO/CeO2 were synthesized by thermal decomposition method. The decomposition temperature and formation of composite material were confirmed by the thermogravimetric analysis (TGA) before the synthesis process. The prepared samples were characterized by different techniques. The structural and morphological properties of ZnO/CeO2 nanorods were confirmed by X-ray diffraction (XRD) and high resolution scanning electron microscopy (HR-SEM). The chemical composition and specific surface area analysis were done by energy dispersive X-ray spectroscopy (EDX) and Brunauer–Emmett–Teller (BET) method. Further the catalyst was used for photocatalytic degradation of organic dye under visible light irradiation

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Enhanced Visible Light Photocatalytic Degradation of Fe-Doped ZnO Nanoparticles For Organic Dyes

10.21203/rs.3.rs-173224/v1 ◽

2021 ◽

Author(s):

Senthilkumar M ◽

C. Arunagiri

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Organic Dyes ◽

Chemical Precipitation ◽

Precipitation Method ◽

Photocatalytic Efficiency ◽

X Ray Diffraction ◽

X Ray ◽

Vis Spectroscopy ◽

Visible Light Photocatalytic

Abstract FexZn1-xO (x = 0, 0.05, 0.075, 0.1 M) nanoparticles based photocatalysts were synthesized by a chemical precipitation method and characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive X-ray emission (EDX) and UV–Vis spectroscopy. The photocatalytic efficiency of FexZn1-xO catalysts was assessed under visible light irradiation using the degradation of methylene blue (MB) and methyl orange (MO) dye in aqueous solution. The present investigation shows that the effect of optimized parameters (pH, catalyst dosage and initial dye concentration) and doping concentrations plays significant role in photocatalytic activity. The detailed photocatalytic mechanism for the enhancement of photocatalytic activity has also been proposed.

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REVO4 (RE=La, Pr, Nd) nanocrystals: Synthesis and investigation of photocatalytic degradation of some dyes

Vietnam Journal of Catalysis and Adsorption ◽

10.51316/jca.2021.055 ◽

2021 ◽

Vol 10 (3) ◽

pp. 82-86

Author(s):

Hai Nguyen Van ◽

Huong Nguyen Thi

Keyword(s):

Electron Microscope ◽

Scanning Electron Microscope ◽

Visible Light ◽

Photocatalytic Degradation ◽

Hydrothermal Method ◽

Organic Dyes ◽

X Ray Diffraction ◽

X Ray ◽

Photocatalytic Activities ◽

Scanning Electron

In this, work, a series of REVO4 (RE = La, Pr, Nd) nanoparticles were successfully fabricated by the hydrothermal method. The as-synthesized REVO4 nanoparticles were characterized by various techniques of X-ray diffraction (XRD), scanning electron microscope (SEM) and energy dispersive X-ray spectroscopy (EDX). The photocatalytic activities of obtained products were investigated by photodegradation of moderacid red RS and direct yellow GX under visible light. The NdVO4 photocatalyst showed higher discoloration of organic dyes than LaVO4 and PrVO4. About 64% moderacid red RS was degraded within 150 minutes catalyzed by the catalyst NdVO4.

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Green synthesized Ag-TiO2 for degradation of organic dye through visible light driven photo-reactor and its kinetics

International Journal of Chemical Reactor Engineering ◽

10.1515/ijcre-2021-0111 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Titikshya Mohapatra ◽

Sakshi Manekar ◽

Vijyendra Kumar Sahu ◽

Ashwini Kumar Soni ◽

Sudip Banerjee ◽

...

Keyword(s):

Visible Light ◽

Mangifera Indica ◽

Band Gap Energy ◽

Photo Degradation ◽

X Ray ◽

Green Approach ◽

Vis Spectroscopy ◽

Rate Of Reaction ◽

Visible Light Driven ◽

Modification Of Titanium

Abstract This study reports a green approach for the modification of titanium dioxide (TiO2) nanoparticles with immobilization of silver nanoparticles. One of the natural sources i.e., Mangifera indica leaf extract was utilized as reducing and capping agent for the fabrication of Ag-TiO2 nanocatalyst. Further, the surface morphology and band-gap energy of prepared Ag-TiO2 were analyzed by Scanning Electron Microscopy (SEM), Energy Dispersive X-ray Spectroscopy (EDS) and UV–Vis spectroscopy. Also, it was characterized by X-ray Powder Diffraction (XRD) which provides the information regarding the crystallinity of the Ag-TiO2. Subsequently, photo activity of Ag-TiO2 was investigated for the degradation of methylene blue (MB) dye wastewater through visible light driven photoreactor. The Ag-TiO2 provided highest (68%) of photo-degradation efficiency within 110 min for 7.81 × 10−5 mol/L initial MB concentration at pH 8 by using 0.19 g/L photocatalyst. Further, addition of 10 mM H2O2 boost up the MB photodegradation to 74%. The kinetic study confirmed the MB degradation followed first order rate of reaction.

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W-Doped TiO2 Preparation and Photocatalytic Degradation of Guaiacol

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.513-517.33 ◽

2014 ◽

Vol 513-517 ◽

pp. 33-36 ◽

Cited By ~ 3

Author(s):

Zi Chang Xie ◽

Ying Wang ◽

Peng Wang ◽

Lei Zhang

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Photocatalytic Degradation ◽

Degradation Rate ◽

Amorphous State ◽

X Ray Diffraction ◽

Model Compounds ◽

Plant Fibers ◽

X Ray ◽

Crystallite Structure

In this paper, W-doped TiO2 (W-TiO2) powder was prepared in hydrothermal method by mixing TiO2 and ammonium metatungstate. The catalysts were characterized by X-ray diffraction and ultraviolet spectrophotometer. The results displayed that W-TiO2 showed an anatase crystallite structure with 2 % W content. W-element in W-TiO2 was amorphous state. The guaiacol was degraded with the W-TiO2 in the visible light. It was a model compounds of lignin existed in the plant fibers. The degradation rate of guaiacol was increased with the photocatalytic time, as high as 88.21 % after 360 min irradiation. It was concluded that the W-TiO2 had an obvious photocatalytic activity under visible light. It can be used in the photocatalytic degradation of lignin.

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Microwave-assisted preparation of ZnS and ZnSe nanocrystals with different morphologies for photodegradation process of organic dyes

Proceedings 17th International Conference on Microwave and High Frequency Heating ◽

10.4995/ampere2019.2019.9998 ◽

2019 ◽

Author(s):

Katarzyna Matras-Postolek ◽

A. Zaba ◽

S. Sovinska ◽

D. Bogdal

Keyword(s):

Electron Microscopy ◽

Photoelectron Spectroscopy ◽

Organic Dyes ◽

Zinc Sulphide ◽

Conventional Heating ◽

Bet Surface Area ◽

X Ray Diffraction ◽

X Ray ◽

Transmission Electron ◽

Vis Spectroscopy

Zinc sulphide (ZnS) and zinc selenide (ZnSe) and manganese-doped and un-doped with different morphologies from 1D do 3D microflowers were successfully fabricated in only a few minutes by solvothermal reactions under microwave irradiation. In order to compare the effect of microwave heating on the properties of obtained nanocrystals, additionally the synthesis under conventional heating was conducted additionally in similar conditions. The obtained nanocrystals were systematically characterized in terms of structural and optical properties using X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), diffuse reflectance UV-Vis spectroscopy (DR UV-Vis), Fourier-transform infrared spectroscopy (FT-IR), photoluminescence spectroscopy (PL), X-ray photoelectron spectroscopy (XPS) and Brunauer-Emmett-Teller (BET) surface area analysis. The photocatalytic activity of ZnSe, ZnS, ZnS:Mn and ZnSe:Mn nanocrystals with different morphologies was evaluated by the degradation of methyl orange (MO) and Rhodamine 6G (R6G), respectively. The results show that Mn doped NCs samples had higher coefficient of degradation of organic dyes under ultraviolet irradiation (UV).

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Starfish-like Au–CdS hybrids for the highly efficient photocatalytic degradation of organic dyes

RSC Advances ◽

10.1039/c4ra07230h ◽

2014 ◽

Vol 4 (80) ◽

pp. 42441-42444 ◽

Cited By ~ 8

Author(s):

Xinyu Wang ◽

Yulong Ying ◽

Jiahuan Lei ◽

Pan Hu ◽

Xinsheng Peng

Keyword(s):

Visible Light ◽

Photocatalytic Degradation ◽

Au Nanoparticles ◽

Organic Dyes ◽

Highly Efficient ◽

Self Assembling

A novel starfish-like Au–CdS heterostructures are constructed by a simple self-assembling method with centered Au nanoparticles, and exhibit highly efficient visible light photodegradation of organic dyes.

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