Photocatalytic degradation of bisphenol A using titanium dioxide@nanodiamond composites under UV light illumination

This paper presents a novel approach for preparing titanium dioxide nanotube arrays (TNTs) loaded with highly dispersed Br through an ultrasound aided photochemical route. The content of Br doped on the arrays was controlled by changing the concentration of NaBr and the ultrasound time. The Br doped TiO2nanotube arrays were characterized by SEM, XRD and UV–Vis spectrum. Doping the bromine did not basically affect the morphology of the surface of the TNTs, but part of the anatase phase transformed into rutile phase, which led to the formation of the mixed crystal and increased the photocatalytic activity. The results showed that Br doping significantly enhanced the photocatalytic degradation rate of titanium dioxide nanotube arrays under UV-light irradiation. The main factors which affected photocatalytic degradation of sugar wastewater were the illumination time and pH. The results showed that the longer the exposure time was, the initial pH of wastewater was more favorable to photocatalytic degradation of the sugar wastewater for the Br-TiO2nanotube arrays, and compared to undoped TiO2nanotube arrays Br doped TiO2nanotube arrays had better photocatalytic properties.

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Direct photolysis and photocatalytic degradation of 2-amino-5-chloropyridine

Journal of the Serbian Chemical Society ◽

10.2298/jsc0312961a ◽

2003 ◽

Vol 68 (12) ◽

pp. 961-970 ◽

Cited By ~ 3

Author(s):

Biljana Abramovic ◽

Vesna Anderluh ◽

Andjelka Topalov ◽

Ferenc Gaal

Keyword(s):

Titanium Dioxide ◽

Photocatalytic Degradation ◽

Uv Light ◽

Parent Compound ◽

Analytical Techniques ◽

Direct Photolysis ◽

Pyridine Moiety ◽

Initial Substrate ◽

Zero Order Reaction ◽

Degradation Reaction

The direct photolysis and photocatalytic degradation of a pyridine pesticide analogue, 2-amino-5-chloropyridine, were investigated employing different analytical techniques ? potentiometry, for monitoring the pH and chloride genera- tion, spectrophotometry, for studying the degradation of the pyridine moiety, ion chromatography, for monitoring nitrate formation, and total organic carbon analysis for investigating the efficiency of the process. The photocatalytic degradation was studied in aqueous suspensions of titanium dioxide under illumination by UV light. It was found that chloride evolution was a zero-order reaction which takes place by direct photolysis, in that way differing from the degradation of the pyridine moiety, which takes place in the presence of titanium dioxide. Changes in pH during degradation indicate the formation of acidic intermediates and nitrate in addition to chloride. The effect of the initial substrate concentration was also investigated by monitoring the reaction of chloride generation as well as the degradation reaction of the pyridine moiety. It was found that degradation of the parent compound (2.5 mmol/dm3) by direct photolysis is completed in about 20 minutes, and of the pyridine moety by photocatalytic degradation in about nine hours. Based on the obtained data a possible reaction mechanism is proposed.

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Cobalt Oxide-Modified Titanium Dioxide Nanoparticle Photocatalyst for Degradation of 2,4-Dichlorophenoxyacetic Acid

Indonesian Journal of Chemistry ◽

10.22146/ijc.22624 ◽

2017 ◽

Vol 17 (2) ◽

pp. 284 ◽

Cited By ~ 1

Author(s):

Leny Yuliati ◽

Nur Azmina Roslan ◽

Wai Ruu Siah ◽

Hendrik Oktendy Lintang

Keyword(s):

Titanium Dioxide ◽

Photocatalytic Activity ◽

Photocatalytic Degradation ◽

Cobalt Oxide ◽

Uv Light ◽

Dichlorophenoxyacetic Acid ◽

Photocatalytic Reaction ◽

Impregnation Method ◽

Titanium Dioxide Nanoparticle ◽

2,4 Dichlorophenoxyacetic Acid

2,4-dichlorophenoxyacetic acid (2,4-D) has been recognized as a possibly carcinogenic compound to human, therefore, 2,4-D should be treated before it is discharged to the environment. Photocatalytic degradation of 2,4-D has been proposed as one of the best methods that offer environmentally safe process. In the present research, titanium dioxide (TiO2) was modified with cobalt oxide (CoO) and tested for photocatalytic degradation of 2,4-D under UV light irradiation. Different amounts of CoO (0.1, 0.5, 1 and 5 mol%) were added onto TiO2 by an impregnation method. The photocatalytic reaction was monitored and analyzed by measurement of 2,4-D absorbance using UV spectrophotometer. After 1 h photocatalytic reaction, it was confirmed that the sample with low loading of 0.1 mol% gave the highest photocatalytic activity among the bare and modified TiO2 photocatalysts. The photocatalytic activity was decreased with the increase of CoO loading, suggesting that the optimum amount of CoO was an important factor to improve the performance of TiO2. Based on fluorescence spectroscopy, such addition of CoO resulted in the reduced emission intensity, which showed the successful decrease in the electron-hole recombination.

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Enhanced ofloxacin degradation efficiency on porous CeTi2O6 photocatalyst-CTAB induced porosity

Current Nanoscience ◽

10.2174/1573413716999200511130328 ◽

2020 ◽

Vol 16 ◽

Author(s):

Lili Yang ◽

Chuanguo Li ◽

Wenjie Zhang

Keyword(s):

Electron Microscopy ◽

Porous Structure ◽

Photocatalytic Degradation ◽

Surface Area ◽

Organic Pollutants ◽

Photoelectron Spectroscopy ◽

Photocatalytic Oxidation ◽

Uv Light ◽

Light Illumination ◽

X Ray

BACKGROUND: Photocatalytic oxidation of organic pollutants in the environment has been studied for more than half a century. Titanate has the activity on degradation of organic pollutants under UV light illumination. Template directed sol-gel method is capable of producing porous structure in titanate during high temperature thermal treatment. METHODS: The materials were characterized using X-ray powder diffraction, transmission electron microscopy, scanning electron microscopy, surface area and pore size analyses, UV-Visible spectrometry, and X-ray photoelectron spectroscopy. Photocatalytic activity of the CeTi2O6 material was evaluated through ofloxacin degradation. RESULTS: Brannerite structured CeTi2O6 was the major component in the samples, and the addition of CTAB caused a slight growth of CeTi2O6 crystals. Porous structure formed in the porous sample after the removal of CTAB template, and the surface area and pore volume were greatly enlarged. The first order reaction rate constant for photocatalytic degradation of ofloxacin was 9.60×10-3 min-1 on the nonporous CeTi2O6 sample, and it was as large as 2.44×10-2 min-1 on the porous CeTi2O6 sample. The addition of CTAB can influence the physico-chemical properties of the porous CeTi2O6, such as the improved activity on photocatalytic degradation of ofloxacin. CONCLUSION: The CeTi2O6 samples were composed of majority brannerite CeTi2O6, and CeTi2O6 crystallite sizes for the nonporous and porous samples were 38.1 and 43.2 nm. The burning up of CTAB during calcination produced abundant pores in the porous material. After 50 min of reaction, photocatalytic degradation efficiencies on the nonporous and porous CeTi2O6 samples were 38.1% and 70.5%.

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

Journal of Nanomaterials ◽

10.1155/2015/538275 ◽

2015 ◽

Vol 2015 ◽

pp. 1-5 ◽

Cited By ~ 2

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.

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Effect of Various Additives on Photocatalytic Degradation of 4-Nitrophenol

E-Journal of Chemistry ◽

10.1155/2009/248548 ◽

2009 ◽

Vol 6 (s1) ◽

pp. S422-S428 ◽

Cited By ~ 4

Author(s):

Kashif Naeem ◽

Feng Ouyang

Keyword(s):

Titanium Dioxide ◽

Photocatalytic Degradation ◽

Rice Husk ◽

Uv Light ◽

Aqueous Suspension ◽

Degradation Efficiency ◽

Optimal Amount ◽

Supporting Materials ◽

Better Than

The photocatalytic degradation of 4-nitrophenol (4-NP) assisted by titanium dioxide (TiO2) was investigated in aqueous suspension under irradiation by UV light. The effect of different supporting materials mixed physically with TiO2on the photocatalytic degradation of 4-NP has been studied. TiO2with all supports exhibits good degradation efficiency of 4-NP and was better than TiO2alone. The addition of SiO2and ZSM-5 only caused a little change in 4-NP degradation. However, degradation of 4-NP was improved from 34.89% to 60.53% within 120 min photocatalysis in the presence of optimal amount of AC. The degradation was also fairly enhanced in the presence of cheaper rice husk and the activity was closed to AC.

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Highly-Organized One-Dimensional Copper-Doped Titanium Dioxide Nanotubes for Photoelectrocatalytic Degradation of Acid Orange 52

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.801.285 ◽

2019 ◽

Vol 801 ◽

pp. 285-291 ◽

Cited By ~ 1

Author(s):

Edgar Clyde R. Lopez ◽

Vince Aron F. Cleofe ◽

Rio Ysabel A. Cañal ◽

Kristoffer Francis P. Boado ◽

Jem Valerie D. Perez

Keyword(s):

Titanium Dioxide ◽

Uv Light ◽

Tube Length ◽

Light Illumination ◽

Order Kinetic ◽

One Pot ◽

Titanium Dioxide Nanotubes ◽

Acid Orange ◽

One Dimensional ◽

Doped Titanium Dioxide

Highly-organized one-dimensional arrays of copper-doped titanium dioxide nanotubes (Cu-TiNTs) were synthesized in a one-pot approach by double anodization of titanium sheets. Field-emission scanning electron microscopy showed that Cu-TiNTs have an average inner diameter of 52.13 nm, a wall thickness of 14.28 nm, and a tube length of 0.6401 μm. Fourier-transform infrared spectroscopy confirmed the presence of characteristic O-Ti-O bond of TiO2. X-ray fluorescence spectroscopy confirmed copper-doping with an average dopant loading of 0.0248%. Even at this low dopant loading, Cu-TiNTs were shown to be photo-active in degrading Acid Orange 52 (AO 52) under UV light illumination. The kinetic profiles of AO 52 photoelectrochemical degradation were best described by the pseudo-first-order kinetic model (R2 ≥ 0.991) with kinetic constants 9.42 x 10-3 min-1 for Cu-TiNTs as compared to 6.04 x 10-3 min-1 for pristine TiNTs. Overall, doping pristine TiNTs with Cu was shown to enhance its photoelectrocatalytic properties in degrading textile dyes such as AO 52.

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