Nitrogen-Doped Nano-TiO2 Ceramic Film: Fabrication and Application to Photocatalysis

Owing to the defects of the fixed TiO2 photocatalysts, the research employed the approach of anodic oxidation to produce high efficiend N-TiO2/Ti ceramic film oxidized on the surface of titanium, in order to make the absorbable spectrum of light catalyst spread to the visible region and constrain the high recombination rate of electron-hole pairs during photoreaction. The surface appearance and the distribution of elements have been checked with scanning electron microscopy and EPMA. The microcrystal structure of the films has been checked with XRD. The results showed that the main components of nitrogen-doped catalyzer were rutile and anatase, meanwhile, the nitrogen element distributing on the film was fairly uniform. Films of N-TiO2 photocatalysis reduction K2CrO4 revealed that with the amount of N-contained increased, the rate of reduction K2CrO4 decreased under ultraviolet light while that increased under visible light. It was found that the highest reduction rate of K2CrO4 was achieved through an optimal (NH4)2S2O8 dosage of 0.4g/L in ceramic film prepared processes.

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Preparation and Photocatalysis of Sulfur-Doped Nano-TiO2/Ti Film

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.177.281 ◽

2010 ◽

Vol 177 ◽

pp. 281-283 ◽

Cited By ~ 3

Author(s):

Yan Li Jiang ◽

Yan Liu ◽

Li Juan Yang ◽

Guo Qing Li ◽

Hui Ling Liu

Keyword(s):

Electron Microscopy ◽

Visible Region ◽

Reduction Rate ◽

Electron Hole ◽

Surface Appearance ◽

Tio2 Photocatalysts ◽

Ceramic Film ◽

Distribution Of Elements ◽

Main Components ◽

Scanning Electron

Owing to the defects of the fixed TiO2 photocatalysts, the research employed the approach of anodic oxidation to produce high efficiend S-TiO2/Ti ceramic film oxidized on the surface of titanium, in order to make the absorbable spectrum of light catalyst spread to the visible region and constrain the high recombination rate of electron-hole pairs during photoreaction. The surface appearance and the distribution of elements have been checked with scanning electron microscopy. The microcrystal structure of the films has been checked with XRD. The results showed that the main components of sulfur-doped catalyzer were rutile and anatase, meanwhile, the sulfur element distributing on the film was fairly uniform. Films of S-TiO2 photocatalysis reduction K2CrO4 revealed that with the amount of S-contained increased, the rate of reduction K2CrO4 decreased under ultraviolet light while that increased under visible light. It was found that the highest reduction rate of K2CrO4 was achieved through an optimal Na2S2O3 dosage of 0.6g/L in ceramic film prepared processes.

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Preparation and Photocatalytic Property of WO3-TiO2 /Ti Ceramic Film via Anodic Oxidation Treatment

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.368-372.1500 ◽

2008 ◽

Vol 368-372 ◽

pp. 1500-1502 ◽

Cited By ~ 3

Author(s):

Yan Li Jiang ◽

Hui Ling Liu ◽

Zhao Hua Jiang ◽

Zhong Ping Yao

Keyword(s):

Visible Light ◽

Anodic Oxidation ◽

Rhodamine B ◽

Recombination Rate ◽

Visible Region ◽

Photocatalytic Property ◽

Electron Hole ◽

Ceramic Film ◽

High Efficient ◽

Anodic Oxidation Treatment

The high efficient WO3-TiO2/Ti ceramic film was prepared on the surface of titanium by the approach of anodic oxidation in order to make the absorbable spectrum of catalyst spread to the visible region and restrain the high recombination rate of electron-hole pairs during photoreaction. The surface morphology and the distribution of elements were studied with scanning electron microscopy and energy dispersive spectroscopy. The phase composition of the films was investigated with XRD. The results showed that the main components in the coating were WO3, rutile TiO2 and anatase TiO2. The compound WO3-TiO2/Ti ceramic film enlarged the range of the reacting visible light and increased the absorbing intensity. The rhodamine B was successfully photodegraded under visible light irradiation by WO3-TiO2/Ti catalyst films. It was found that the highest degradation rate of rhodamine B was achieved through an optimal W dosage of 4.2 %(wt %) in WO3-TiO2/Ti ceramic film. It was also confirmed that the recombination rate of electron-hole pairs in WO3-TiO2/Ti ceramic film declined due to the existence of WO3 in TiO2/Ti ceramic film.

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Preparation and Photocatalytic Performance for Degradation of Rhodamine B of AgPt/Bi4Ti3O12 Composites

Nanomaterials ◽

10.3390/nano10112206 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2206

Author(s):

Gaoqian Yuan ◽

Gen Zhang ◽

Kezhuo Li ◽

Faliang Li ◽

Yunbo Cao ◽

...

Keyword(s):

Visible Light ◽

Noble Metal ◽

Rhodamine B ◽

Photocatalytic Performance ◽

Bimetallic Nanoparticles ◽

Resonance Effect ◽

Visible Region ◽

Photogenerated Electron ◽

Pt Nanoparticles ◽

Electron Hole

Loading a noble metal on Bi4Ti3O12 could enable the formation of the Schottky barrier at the interface between the former and the latter, which causes electrons to be trapped and inhibits the recombination of photoelectrons and photoholes. In this paper, AgPt/Bi4Ti3O12 composite photocatalysts were prepared using the photoreduction method, and the effects of the type and content of noble metal on the photocatalytic performance of the catalysts were investigated. The photocatalytic degradation of rhodamine B (RhB) showed that the loading of AgPt bimetallic nanoparticles significantly improved the catalytic performance of Bi4Ti3O12. When 0.10 wt% noble metal was loaded, the degradation rate for RhB of Ag0.7Pt0.3/Bi4Ti3O12 was 0.027 min−1, which was respectively about 2, 1.7 and 3.7 times as that of Ag/Bi4Ti3O12, Pt/Bi3Ti4O12 and Bi4Ti3O12. The reasons may be attributed as follows: (i) the utilization of visible light was enhanced due to the surface plasmon resonance effect of Ag and Pt in the visible region; (ii) Ag nanoparticles mainly acted as electron acceptors to restrain the recombination of photogenerated electron-hole pairs under visible light irradiation; and (iii) Pt nanoparticles acted as electron cocatalysts to further suppress the recombination of photogenerated electron-hole pairs. The photocatalytic performance of Ag0.7Pt0.3/Bi4Ti3O12 was superior to that of Ag/Bi4Ti3O12 and Pt/Bi3Ti4O12 owing to the synergistic effect between Ag and Pt nanoparticles.

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Antimycotoxigenic Activity of Beetroot Extracts against Altenaria alternata Mycotoxins on Potato Crop

Applied Sciences ◽

10.3390/app11094239 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4239

Author(s):

Nesrine H. Youssef ◽

Sameer H. Qari ◽

Said I. Behiry ◽

Eldessoky S. Dessoky ◽

Ehab I. El-Hallous ◽

...

Keyword(s):

Potato Crop ◽

Reduction Rate ◽

Acid Methyl Ester ◽

Ethanol Extract ◽

Monomethyl Ether ◽

Morphological Identification ◽

Hexadecanoic Acid ◽

Alternariol Monomethyl Ether ◽

Alternaria Species ◽

Main Components

Alternaria species, mainly air-borne fungi, affect potato plants, causing black spots symptoms. Morphological identification, pathogenicity assessment, and internal transcribed spacer (ITS) molecular identification confirmed that all isolates were Alternaria alternata. The annotated sequences were deposited in GenBank under accession numbers MN592771–MN592777. HPLC analysis revealed that the fungal isolates KH3 (133,200 ng/g) and NO3 (212,000 ng/g) produced higher levels of tenuazonic acid (TeA) and alternariol monomethyl ether (AME), respectively. Beet ethanol extract (BEE) and beet methanol extract (BME) at different concentrations were used as antimycotoxins. BME decreased the production of mycotoxins by 66.99–99.79%. The highest TeA reduction rate (99.39%) was reported in the KH3 isolate with 150 µg/mL BME treatment. In comparison, the most effective AME reduction rate (99.79%) was shown in the NO3 isolate with 150 µg/mL BME treatment. In the same way, BEE application resulted in 95.60–99.91% mycotoxin reduction. The highest TeA reduction rate (99.91%) was reported in the KH3 isolate with 150 µg/mL BEE treatment, while the greatest AME reduction rate (99.68%) was shown in the Alam1 isolate with 75 µg/mL BEE treatment. GC-MS analysis showed that the main constituent in BME was the antioxidant compound 1-dodecanamine, n,n-dimethyl with a peak area of 43.75%. In contrast, oxirane, methyl- (23.22%); hexadecanoic acid, methyl ester (10.72%); and n-hexadecanoic acid (7.32%) were the main components in BEE found by GC-MS. They are probably antimicrobial molecules and have an effect on the mycotoxin in general. To our knowledge, this is the first study describing the antimycotoxigenic activity of beet extracts against A. alternata mycotoxins-contaminated potato crops in Egypt, aimed to manage and save the environment.

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Carbon-Doped TiO2 Ceramic Film: Fabrication and Application to Photocatalysis

2009 3rd International Conference on Bioinformatics and Biomedical Engineering ◽

10.1109/icbbe.2009.5162471 ◽

2009 ◽

Author(s):

Yanli Jiang ◽

Chunxiang Li ◽

Huiling Liu ◽

Zhaohua Jiang

Keyword(s):

Doped Tio2 ◽

Carbon Doped ◽

Ceramic Film ◽

Tio2 Ceramic ◽

Film Fabrication

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Enhanced Photocatalytic Reduction of Cr(VI) by Combined Magnetic TiO2-Based NFs and Ammonium Oxalate Hole Scavengers

Catalysts ◽

10.3390/catal9010072 ◽

2019 ◽

Vol 9 (1) ◽

pp. 72 ◽

Cited By ~ 4

Author(s):

Yin-Hsuan Chang ◽

Ming-Chung Wu

Keyword(s):

Organic Contaminants ◽

High Efficiency ◽

Ammonium Oxalate ◽

Reaction Rate Constant ◽

Electron Hole ◽

Tio2 Nanofibers ◽

Tio2 Photocatalysts ◽

Survival And Development ◽

Hole Scavenger ◽

Separation Behavior

Heavy metal pollution of wastewater with coexisting organic contaminants has become a serious threat to human survival and development. In particular, hexavalent chromium, which is released into industrial wastewater, is both toxic and carcinogenic. TiO2 photocatalysts have attracted much attention due to their potential photodegradation and photoreduction abilities. Though TiO2 demonstrates high photocatalytic performance, it is a difficult material to recycle after the photocatalytic reaction. Considering the secondary pollution caused by the photocatalysts, in this study we prepared Ag/Fe3O4/TiO2 nanofibers (NFs) that could be magnetically separated using hydrothermal synthesis, which was considered a benign and effective resolution. For the photocatalytic test, the removal of Cr(VI) was carried out by Ag/Fe3O4/TiO2 nanofibers combined with ammonium oxalate (AO). AO acted as a hole scavenger to enhance the electron-hole separation ability, thereby dramatically enhancing the photoreduction efficiency of Cr(VI). The reaction rate constant for Ag/Fe3O4/TiO2 NFs in the binary system reached 0.260 min−1, 6.95 times of that of Ag/Fe3O4/TiO2 NFs in a single system (0.038 min−1). The optimized Ag/Fe3O4/TiO2 NFs exhibited high efficiency and maintained their photoreduction efficiency at 90% with a recyclability of 87% after five cycles. Hence, taking into account the high magnetic separation behavior, Ag/Fe3O4/TiO2 NFs with a high recycling capability are a potential photocatalyst for wastewater treatment.

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Photocatalytic Liquid-Phase Selective Hydrogenation of 3-Nitrostyrene to 3-vinylaniline of Various Treated-TiO2 Without Use of Reducing Gas

Catalysts ◽

10.3390/catal9040329 ◽

2019 ◽

Vol 9 (4) ◽

pp. 329 ◽

Cited By ~ 1

Author(s):

Okorn Mekasuwandumrong ◽

Saknarin Chaitaworn ◽

Joongjai Panpranot ◽

Piyasan Praserthdam

Keyword(s):

Selective Hydrogenation ◽

Consumption Rate ◽

Rutile Phase ◽

Optimum Amount ◽

Electron Hole ◽

Tio2 Photocatalysts ◽

Reducing Gas ◽

Pl Intensity ◽

Different Gases ◽

Hole Recombination

In this work, we investigate the effect of TiO2 properties on the photocatalytic selective hydrogenation of 3-nitrostyrene (3-NS) to 3-vinylaniline (3-VA). The P25-TiO2 photocatalysts were calcined at 600–900 °C using different gases (Air, N2, and H2) and characterized by XRD, N2 physisorption, XPS, UV-Vis, and PL spectroscopy. In the photocatalytic hydrogenation of 3-nitrostyrene in isopropanol, the selectivity of 3-vinylaniline of the treated TiO2 was almost 100%. A linear correlation between the 3-NS consumption rate and PL intensity was observed. Among the catalysts studied, P25-700-air, which possessed the lowest PL intensity, exhibited the highest photocatalytic activity due to the synergistic effect that resulted from its high crystallinity and the optimum amount of anatase/rutile phase content, leading to the reduction of the electron-hole recombination process.

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Fabrication of a Cu2O-Au-TiO2 Heterostructure with Improved Photocatalytic Performance for the Abatement of Hazardous Toluene and α-Pinene Vapors

Catalysts ◽

10.3390/catal10121434 ◽

2020 ◽

Vol 10 (12) ◽

pp. 1434

Author(s):

Joon Yeob Lee ◽

Jeong-Hak Choi

Keyword(s):

Photoelectron Spectroscopy ◽

Photocatalytic Oxidation ◽

Separation Efficiency ◽

Diffuse Reflectance Spectrum ◽

Visible Region ◽

Pure Tio2 ◽

Great Promise ◽

Light Sources ◽

Electron Hole ◽

X Ray

In the current research, a Cu2O-Au-TiO2 heterostructure was fabricated via a step-wise photodeposition route to determine its possible application in the photocatalytic oxidation of hazardous vapors. The results of electron microscopy and X-ray photoelectron spectroscopy confirm the successful fabrication of the Cu2O-Au-TiO2 heterostructure. Strong absorption in the visible region, along with a slight red-shift in the absorption edge, was observed in the UV–vis diffuse reflectance spectrum of Cu2O-Au-TiO2 composite, which implies that the composite can generate a greater number of photoexcited charges necessary for photocatalytic reaction. Toluene and α-pinene, as common gas contaminants in the indoor atmosphere, were employed to assess the photooxidation efficiency of the Cu2O-Au-TiO2 composite. Importantly, photocatalytic activity results indicate that the Cu2O-Au-TiO2 composite showed excellent photodegradation performance compared to pure TiO2 and Cu2O-TiO2 and Au-TiO2, where photocatalytic efficiency was approximately 92.9% and 99.9% for toluene and α-pinene, respectively, under standard daylight illumination. The increased light-harvesting capacity and boosted separation efficiency of electron-hole pairs were mainly accountable for improved degradation performance of the Cu2O-Au-TiO2 composite. In addition, the degradation efficiencies for toluene and α-pinene by the Cu2O-Au-TiO2 composite were also examined under three different light sources: 0.32 W white, blue and violet LEDs. The findings of this work suggested a great promise of effective photooxidation of gas pollutants by the Cu2O-Au-TiO2 composite.

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The Photocatalytic and Antibacterial Performance of Nitrogen-Doped TiO2: Surface-Structure Dependence and Silver-Deposition Effect

Nanomaterials ◽

10.3390/nano10112261 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2261 ◽

Cited By ~ 2

Author(s):

Abdul Wafi ◽

Erzsébet Szabó-Bárdos ◽

Ottó Horváth ◽

Mihály Pósfai ◽

Éva Makó ◽

...

Keyword(s):

Electron Microscopy ◽

Visible Light ◽

Surface Area ◽

Photocatalytic Performance ◽

Visible Region ◽

Bet Surface Area ◽

Doped Tio2 ◽

X Ray ◽

Nitrogen Doped ◽

Visible Light Driven

Catalysts for visible-light-driven oxidative cleaning processes and antibacterial applications (also in the dark) were developed. In order to extend the photoactivity of titanium dioxide into the visible region, nitrogen-doped TiO2 catalysts with hollow and non-hollow structures were synthesized by co-precipitation (NT-A) and sol–gel (NT-U) methods, respectively. To increase their photocatalytic and antibacterial efficiencies, various amounts of silver were successfully loaded on the surfaces of these catalysts by using a facile photo-deposition technique. Their physical and chemical properties were evaluated by using scanning electron microscopy (SEM), transmission electron microscopy–energy dispersive X-ray spectroscopy (TEM–EDS), Brunauer–Emmett–Teller (BET) surface area, X-ray diffraction (XRD), and diffuse reflectance spectra (DRS). The photocatalytic performances of the synthesized catalysts were examined in coumarin and 1,4-hydroquinone solutions. The results showed that the hollow structure of NT-A played an important role in obtaining high specific surface area and appreciable photoactivity. In addition, Ag-loading on the surface of non-hollow structured NT-U could double the photocatalytic performance with an optimum Ag concentration of 10−6 mol g−1, while a slight but monotonous decrease was caused in this respect for the hollow surface of NTA upon increasing Ag concentration. Comparing the catalysts with different structures regarding the photocatalytic performance, silverized non-hollow NT-U proved competitive with the hollow NT-A catalyst without Ag-loading for efficient visible-light-driven photocatalytic oxidative degradations. The former one, due to the silver nanoparticles on the catalyst surface, displayed an appreciable antibacterial activity, which was comparable to that of a reference material practically applied for disinfection in polymer coatings.

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