Magnetic field assisted photocatalytic degradation of organic dyes in the presence of Ag/TiO2 coated composite

2013 ◽  
Vol 67 (4) ◽  
pp. 722-728 ◽  
Author(s):  
Jian Wang ◽  
Jingqun Gao ◽  
Jun Wang ◽  
Yu Zhai ◽  
Zhongxing Wang ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Rotational Speed ◽  
Organic Dyes ◽  
Dye Degradation ◽  
Uv Light ◽  
Irradiation Time ◽  
Sol Gel ◽  
Heat Treated

Ag/TiO2 coated composite was prepared via sol-gel method in order to elucidate its application in magnetic field assisted photocatalytic degradation of dyes. Through the degradation of organic dyes, the key influences such as Ag amount, heat-treated temperature and time on the photocatalytic activity of Ag/TiO2, as well as UV irradiation time, rotational speed, dye concentration and magnetic sheet number on the photocatalytic degradation were studied. Results showed that the Ag/TiO2 with 25 wt% Ag content heat-treated at 550 °C for 60 min has the best photocatalytic activity. With the increase of UV light irradiation time, rotational speed and magnetic sheet number, the degradation rate is improved. Different dye degradation proved that the method could universally be used.

Synthesis of coral-globular-like composite Ag/TiO2-SnO2 and its photocatalytic degradation of rhodamine B under multiple modes

2017 ◽  
Vol 76 (8) ◽  
pp. 2120-2132 ◽  
Author(s):  
Q. Song ◽  
L. Li ◽  
N. Zhuo ◽  
H. N. Zhang ◽  
X. Chen ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Rhodamine B ◽  
Photoelectron Spectroscopy ◽  
Diffuse Reflectance Spectroscopy ◽  
Organic Dyes ◽  
Uv Light ◽  
Sol Gel ◽  
X Ray ◽  
Tio2 Anatase

Taking cetyltrimethylammonium bromide (CTAB) as the template and using TiO2 as the substrate, coral-globular-like composite Ag/TiO2-SnO2 (CTAB) was successfully synthesized by the sol–gel combined with a temperature-programmed treatment method. X-ray diffraction, scanning electron microscopy (SEM), UV–vis diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, SEM combined with X-ray energy dispersive spectroscopy, and N2 adsorption–desorption tests were employed to characterize samples' crystalline phase, chemical composition, morphology and surface physicochemical properties. Results showed that composites not only had TiO2 anatase structure, but also had some generated SnTiO4, and the silver species was metallic Ag0. Ag/TiO2-SnO2 (CTAB) possessed a coral-globular-like structure with nanosheets in large quantities. The photocatalytic activity of Ag/TiO2-SnO2 (CTAB) had studied by degrading organic dyes under multi-modes, mainly using rhodamine B as the model molecule. Results showed that the coral-globular-like Ag/TiO2-SnO2 (CTAB) was higher photocatalytic activity than that of commercial TiO2, Ag/TiO2-SnO2, TiO2-SnO2 (CTAB), and TiO2-SnO2 under ultraviolet light irradiation. Moreover, Ag/TiO2-SnO2 (CTAB) composite can significantly affect the photocatalytic degradation under multi-modes including UV light, visible light, simulated solar light and microwave-assisted irradiation. Meanwhile, the photocatalytic activity of Ag/TiO2-SnO2 (CTAB) was maintained even after three cycles, indicating that the catalyst had good usability.

Morphologic, Photocatalytic and Antibacterial Properties of ZnO-TiO2 Sol-Gel System

2018 ◽  
Vol 762 ◽  
pp. 278-282
Author(s):  
Anzelms Zukuls ◽  
Gundars Mežinskis ◽  
Aigars Reinis ◽  
Ingus Skadins ◽  
Juta Kroica ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Uv Light ◽  
Sol Gel ◽  
Antibacterial Properties ◽  
Ultra Violet ◽  
Properties Of Coatings ◽  
Force Microscopy ◽  
Glass Slides ◽  
Heat Treated ◽  
Colour Changes

Prepared and heat-treated sol-gel ZnO-TiO2 coatings onto microscope glass slides were characterised by atomic force microscopy (AFM), scanning electron microscopy (SEM), as well as absorption spectra of light has been obtained. Thermally treated xerogels were characterised by X-ray diffraction (XRD). As well as their photocatalytic activity using methyl orange (MO) and observing the colour changes over the time in visible light (VIS) and ultra violet (UV) light has been determined. The influence of ZnO concentration on morphology, photocatalytic activity and antibacterial properties of coatings was analysed. The growth of S. epidermidis on the surface of the samples was inhibited due to photocatalytic properties of coatings.

scholarly journals Facile Synthesis of “Boron-Doped” Carbon Dots and Their Application in Visible-Light-Driven Photocatalytic Degradation of Organic Dyes

Nanomaterials ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1560 ◽  
Author(s):  
Zhili Peng ◽  
Yiqun Zhou ◽  
Chunyu Ji ◽  
Joel Pardo ◽  
Keenan J. Mintz ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Carbon Dots ◽  
Organic Dyes ◽  
Dye Degradation ◽  
Average Diameter ◽  
Spherical Particles ◽  
Promising Alternative ◽  
Excellent Photocatalytic Activity ◽  
Doped Carbon Dots

Carbon dots (C-dots) were facilely fabricated via a hydrothermal method and fully characterized. Our study shows that the as-synthesized C-dots are nontoxic, negatively charged spherical particles (average diameter 4.7 nm) with excellent water dispersion ability. Furthermore, the C-dots have a rich presence of surface functionalities such as hydroxyls and carboxyls as well as amines. The significance of the C-dots as highly efficient photocatalysts for rhodamine B (RhB) and methylene blue (MB) degradation was explored. The C-dots demonstrate excellent photocatalytic activity, achieving 100% of RhB and MB degradation within 170 min. The degradation rate constants for RhB and MB were 1.8 × 10−2 and 2.4 × 10−2 min−1, respectively. The photocatalytic degradation performances of the C-dots are comparable to those metal-based photocatalysts and generally better than previously reported C-dots photocatalysts. Collectively considering the excellent photocatalytic activity toward organic dye degradation, as well as the fact that they are facilely synthesized with no need of further doping, compositing, and tedious purification and separation, the C-dots fabricated in this work are demonstrated to be a promising alternative for pollutant degradation and environment protection.

scholarly journals Preparation and Photocatalytic Activity of TiO2/Fine Char for Removal of Rhodamine B

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Mingjie Ma ◽  
Weijie Guo ◽  
Zhengpeng Yang ◽  
Shanxiu Huang ◽  
Guanyu Wang
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Rhodamine B ◽  
Uv Light ◽  
Sol Gel ◽  
Tetrabutyl Titanate ◽  
Light Illumination ◽  
X Ray Diffraction ◽  
X Ray ◽  
Uv Light Irradiation

TiO2/fine char (FC) photocatalyst was prepared via sol-gel method with tetrabutyl titanate as the precursor and FC as the carrier. The structural property of TiO2/FC photocatalyst was investigated by X-ray diffraction (XRD) and scanning electron microscopy (SEM), and the photocatalytic activity of TiO2/FC was evaluated by photocatalytic degradation of rhodamine B (RhB) aqueous solution under UV light irradiation. The results showed that TiO2was successfully coated on the surface of FC, and the TiO2/FC photocatalyst had better photocatalytic efficiency and stability for degradation of RhB under UV light illumination as compared to that of the pure TiO2and FC. The study provided a novel way for the application of FC to the photocatalytic degradation of organic wastes.

Photocatalytic Degradation of Acetaldehyde by Sol-Gel TiO2 Nanoparticles: Effect of the Physicochemical Properties on the Photocatalytic Activity

2011 ◽  
Vol 691 ◽  
pp. 92-98 ◽  
Author(s):  
R. Carrera ◽  
A.L. Vázquez ◽  
S. Castillo ◽  
E.M. Arce Estrada
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Surface Area ◽  
Photocatalytic Oxidation ◽  
Crystal Size ◽  
Uv Light ◽  
High Surface ◽  
Sol Gel ◽  
High Surface Area ◽  
Synthesis Method

Nowadays, nanostructured semiconductor materials offer promising opportunities for a new generation of materials such as TiO2nanoparticles with improved properties for their application in the environmental catalysis field. It is well known that the phocatalytic activity of the TiO2nanoparticles is strongly dependent on the surface area, crystal size, phase composition and synthesis method. Thus, the preparation conditions clearly affect the photocatalytic activity of the TiO2nanoparticles. This work deals with the study of the structure of TiO2nanoparticles that were synthesized by the sol-gel method (using isopropanol as solvent), and calcined at 200 and 500°C. The obtained samples were characterized by the XRD-Rietveld refinement, BET and TEM techniques; and tested in the photodecomposition of acetaldehyde. The evaluations were carried out at room temperature by using CH3CHO (300 ppmv), O2(2.0 %) in helium balance in a quartz glass photoreactor (gas phase) with a 365-UV light lamp. According to the results, the sample that presented the highest activity in the photocatalytic oxidation of acetaldehyde (96.4%) was the one annealed at 200 °C. This sample showed the following proportion of phases: anatase (62.88%) with a tetragonal structure (a=0.3790926, b=0.3790926, c=0.9495732) nm; and b) brookite (37.12%) with an orthorhombic structure (a=0.9167624, b=0.5416461, c=0.5210546) nm. The surface area was 189 m2/g and the average crystal size was 7.03 nm. From the results, it can be seen that this material showed high activity in the photocatalytic degradation of acetaldehyde because of: the presence of a mixture of the anatase (higher proportion) and brookite phases, nanometric crystal size and high surface area obtained in this TiO2material. According to the aforementioned, this material can be considered as a good option for the decomposition of acetaldehyde and other volatile organic compounds (VOCs) in confined spaces.

scholarly journals Diatom Biosilica Doped with Palladium(II) Chloride Nanoparticles as New Efficient Photocatalysts for Methyl Orange Degradation

2021 ◽  
Vol 22 (13) ◽  
pp. 6734
Author(s):  
Myroslav Sprynskyy ◽  
Paulina Szczyglewska ◽  
Izabela Wojtczak ◽  
Izabela Nowak ◽  
Andrzej Witkowski ◽  
...  
Keyword(s):  
Methyl Orange ◽  
Photocatalytic Degradation ◽  
Dye Degradation ◽  
Uv Light ◽  
Irradiation Time ◽  
Water Solution ◽  
Degradation Process ◽  
Solution Temperature ◽  
Scattering Effect ◽  
Light Excitation

A new catalyst based on biosilica doped with palladium(II) chloride nanoparticles was prepared and tested for efficient degradation of methyl orange (MO) in water solution under UV light excitation. The obtained photocatalyst was characterized by X-ray diffraction, TEM and N2 adsorption/desorption isotherms. The photocatalytic degradation process was studied as a function of pH of the solution, temperature, UV irradiation time, and MO initial concentration. The possibilities of recycling and durability of the prepared photocatalysts were also tested. Products of photocatalytic degradation were identified by liquid chromatography–mass spectrometry analyses. The photocatalyst exhibited excellent photodegradation activity toward MO degradation under UV light irradiation. Rapid photocatalytic degradation was found to take place within one minute with an efficiency of 85% reaching over 98% after 75 min. The proposed mechanism of photodegradation is based on the assumption that both HO• and O2•− radicals, as strongly oxidizing species that can participate in the dye degradation reaction, are generated by the attacks of photons emitted from diatom biosilica (photonic scattering effect) under the influence of UV light excitation. The degradation efficiency significantly increases as the intensity of photons emitted from biosilica is enhanced by palladium(II) chloride nanoparticles immobilized on biosilica (synergetic photonic scattering effect).

Photocatalytic Activity of Transition Metal Ion Doped Titania for Amaranth Dye Degradation

2012 ◽  
Vol 712 ◽  
pp. 85-104 ◽  
Author(s):  
Neetu Divya ◽  
Ajay Bansal ◽  
Asim K. Jana
Keyword(s):  
Photocatalytic Activity ◽  
Transition Metal ◽  
Photocatalytic Degradation ◽  
Metal Ion ◽  
Dye Degradation ◽  
Irradiation Time ◽  
Impregnation Method ◽  
Tem Analysis ◽  
Toc Removal ◽  
Doped Titania

nanosized titania catalyst and transition metal doped titania photocatalysts such as TiO2/Ag, TiO2/Cu and TiO2/Ag/Cu were used for photocatalytic degradation of Amaranth. Doping of titania was done with impregnation method. Photocatalytic activity was checked in terms of percentages of decolorization, COD removal and TOC removal. It was found that TiO2/Ag/Cu doped photocatalyst was more effective for Amaranth dye degradation under feasible treatment conditions. For decolorization, Amaranth took irradiation time of 210 min with UV/H2O2 but it took only 60 min with TiO2/Ag/Cu doped photocatalyst. Only 29% COD and 49% TOC removal were achieved with homogeneous photodegradation, whereas with TiO2/Ag/Cu heterogeneous photodegradation, 100% COD and 98% TOC removal was achieved in 9h for 50 ppm aqueous Amaranth solution. The relative electrical energy consumption per order of magnitude for photocatalytic degradation of Amaranth was considerably lower with TiO2/Ag/Cu catalyst than that with UV/H2O2 and other combinations of doped photocatalyst. The photocatalysts were characterized using XRD and TEM analysis.

scholarly journals TiO2/SiO2Composite Films Immobilized on Foam Nickel Substrate for the Photocatalytic Degradation of Gaseous Acetaldehyde

2008 ◽  
Vol 2008 ◽  
pp. 1-8 ◽  
Author(s):  
Hai Hu ◽  
Wenjun Xiao ◽  
Jian Yuan ◽  
Jianwei Shi ◽  
Wenfeng Shangguan
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Transition Layer ◽  
Uv Light ◽  
Sol Gel ◽  
Composite Films ◽  
Nickel Substrate ◽  
Degradation Reactions ◽  
Degradation Ratio ◽  
Photocatalytic Activities

The photocatalyst anatase titanium dioxide (TiO2) films were immobilized via sol-gel technique on foam nickel modified withSiO2films as transition layer (indicated asTiO2/SiO2films). The structural properties ofTiO2/SiO2composite films were characterized using TG-DSC, XRD, FE-SEM, and BET. The photocatalytic activities of immobilizedTiO2/SiO2films were tested through photocatalytic degradation reactions of gaseous acetaldehyde under ultraviolet (UV) light irradiation. The substrate modification with transition layer ofSiO2films improved the specific surface area (SSA) of substrate and the acetaldehyde adsorption on photocatalyst film enormously and resulted in great enhancement of photocatalytic activity and stability. The degradation ratio of gaseous acetaldehyde (concentration of 100 ppmv) onTiO2/SiO2photocatalysts reached 100% after 100 minutes of irradiation. The photocatalytic activity ofTiO2/SiO2films reduced about 15% after 9 consecutive runs, which was more stable than that ofTiO2films, and was completely recovered after heating at300∘C for 1 hour.

Preparation Conditions on Adsorption and Photocatalytic Activity of TiO2 Particles Prepared by Sol-Gel Method

2011 ◽  
Vol 230-232 ◽  
pp. 131-135
Author(s):  
Wen Jie Zhang ◽  
Yang Yu
Keyword(s):  
Photocatalytic Activity ◽  
Methyl Orange ◽  
Photocatalytic Degradation ◽  
Degradation Rate ◽  
Irradiation Time ◽  
Sol Gel ◽  
Time Range ◽  
Optimal Composition ◽  
Preparation Conditions ◽  
Sol Gel Process

The amounts of ethanol, HCl and H2O, and also calcination conditions during sol-gel process of preparing TiO2 photocatalyst were investigated. Methyl orange adsorption on TiO2 prepared using different sol compositions is not more than 4% by varying the amount of ethanol, HCl and H2O. The photocatalytic degradation is related to sol composition, and the optimal composition is composed of 10 ml ethanol, 1.0 ml H2O, and 0.1 ml HCl. Calcination temperature and time are also important in TiO2 preparation. The TiO2 particle prepared at 500 °C for 3 h has the optimal photocatalytic activity. In the irradiation time range up to 100 min, photocatalytic degradation rate constantly increases up to 94.2%.

Preparation of TiO2/Bio-Composite Film by Sol-Gel Method in VOCs Photocatalytic Degradation Process

2013 ◽  
Vol 390 ◽  
pp. 552-556 ◽  
Author(s):  
Torpong Kreetachat ◽  
Jittiporn Kruenate ◽  
Kowit Suwannahong
Keyword(s):  
Photocatalytic Activity ◽  
Photocatalytic Degradation ◽  
Uv Light ◽  
Anatase Phase ◽  
Sol Gel ◽  
Composite Films ◽  
Sem Images ◽  
Gel Method ◽  
Sol Gel Method ◽  
Toluene Removal

Biodegradable of polylactic acid (PLA), polybutylene adipate-co-terephthalate (PBAT) and polybutylene succinate (PBS), which were biodegradable aliphatic polyesters, composite films were contained with titanium dioxide (TiO2) as a photocatalyst to evaluate the photocatalytic activity of bidegradable composite films for toluene removal. The synthesized TiO2 was prepared by sol-gel method between titanium isopropoxide with acetic acid. To form the anatase structure, it was calcined at 500°C. TiO2 were added to PLA/PBAT/PBS as a biopolymer blend at 0, 5 and 10 wt% .The TiO2/Bio-composite films were fabricated via blown film technique to produce 40 μm films. Photocatalytic activity efficiency of TiO2/Bio-composite films was performed in an annular closed system under UV light. Since the amount of TiO2 affected the efficiency of the photocatalytic activity, this work was mainly concentrated on the effort to embed the high amount of TiO2 in the biopolymer matrix. The developed photocatalyst was characterized by XRD, UV-Vis spectrophotometer and SEM. The SEM images revealed the high homogeneity of the deposition of TiO2 on the biopolymer matrix. The X-ray diffraction (XRD) ensures the deposition of TiO2 as crystalline anatase phase. In addition, the photocatalytic results shown that the toluene removal efficiencies increased with an increasing TiO2 dosages at 0 wt%, 5 wt%, and 10 wt% , respectively. As aspects, the photocatalytic degradation results showed the highest tolune photocatalytic degradation efficiency of 52.0% at 10 wt% TiO2 .

Sign in / Sign up

Export Citation Format

Share Document