scholarly journals Low-Cost Synthesis of Cu-Modified Immobilized Nanoporous TiO2 for Photocatalytic Degradation of 1H-Benzotriazole

Catalysts ◽  
2019 ◽  
Vol 10 (1) ◽  
pp. 19 ◽  
Author(s):  
Tihana Čižmar ◽  
Ivana Panžić ◽  
Krešimir Salamon ◽  
Ivana Grčić ◽  
Lucija Radetić ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Spin Coating ◽  
Low Cost ◽  
Electrochemical Anodization ◽  
Synthesis Methods ◽  
X Ray Diffraction ◽  
X Ray ◽  
Surface Areas ◽  
Titanium Foils ◽  
The Given

Cu-modified immobilized nanoporous TiO2 photocatalysts, prepared by electrochemical anodization of titanium foils, were obtained via four different synthesis methods: hydrothermal synthesis, anodization with Cu source, electrodeposition, and spin-coating, using two different copper sources, Cu(NO3)2 and Cu(acac)2. The objective of this research was to investigate how copper modifications can improve the photocatalytic activity of immobilized nanoporous TiO2 under the UV/solar light irradiation. The best photocatalytic performances were obtained for Cu-modifications using spin-coating. Therefore, the effect of irradiated catalyst surface areas on the adsorption of model pollutants, methylene blue (MB) and 1H-benzotriazole (BT), was examined for samples with Cu-modification by the spin-coating technique. The mechanisms responsible for increased degradation of MB and BT at high Cu concentrations (0.25 M and 0.5 M) and decreased degradation at low Cu loadings (0.0625 M and 0.125 M) were explained. 1H-benzotriazole was used to study the photocatalytic activity of the given samples because it is highly toxic and present in most water systems. The characterization of the synthesized Cu-modified photocatalysts in terms of phase composition, crystal structure, and morphology were investigated using X-ray Diffraction, Raman Spectroscopy, Scanning Electron Microscopy, and Energy Dispersive X-ray spectroscopy.

scholarly journals Hydrothermal Synthesis of FeOOH and Fe2O3 Modified Self-Organizing Immobilized TiO2 Nanotubes for Photocatalytic Degradation of 1H-Benzotriazole

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1371
Author(s):  
Tihana Čižmar ◽  
Vedran Kojić ◽  
Marko Rukavina ◽  
Lidija Brkljačić ◽  
Krešimir Salamon ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Hydrothermal Synthesis ◽  
Tio2 Nanotubes ◽  
Synthesis Method ◽  
Electrochemical Anodization ◽  
X Ray Diffraction ◽  
X Ray ◽  
Vis Spectroscopy ◽  
Flow Through ◽  
The Given

In this study, titanium dioxide nanotubes were prepared by electrochemical anodization technique and modified with an aqueous solution of FeCl3 using hydrothermal synthesis method to control the amount and distribution of iron compounds on the anatase TiO2 nanotubes. The objective was to synthesize immobilized FeOOH@TiO2 or Fe2O3@TiO2 photocatalysts designed for the flow-through reactor systems; to investigate thermal treatment effect on the photocatalytic efficiency; to determine appropriate Fe-compounds concentration for the maximum photocatalytic activity improvement, and to explain the mechanism responsible for the enhancement. The photocatalysts were tested for the degradation of 1H-benzotriazole in water under UV/solar light irradiation. Up to two times increase in the photocatalytic activity was obtained when TiO2 nanotubes were modified with 0.8 mM Fe. At higher Fe concentrations (8 mM and 80 mM), the photocatalytic activity of the given photocatalysts decreased. To confirm the formation of FeOOH or Fe2O3 species, and to clarify the mechanism of photoactivity, X-ray diffraction (XRD), Raman spectroscopy (RS), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray spectroscopy (EDS) and UV-Vis spectroscopy were used.

scholarly journals Novel, Simple and Low-Cost Preparation of Ba-Modified TiO2 Nanotubes for Diclofenac Degradation under UV/Vis Radiation

Nanomaterials ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 2714
Author(s):  
Mario Bohač ◽  
Tihana Čižmar ◽  
Vedran Kojić ◽  
Jan Marčec ◽  
Krunoslav Juraić ◽  
...  
Keyword(s):  
Tio2 Nanotubes ◽  
Low Cost ◽  
Electrochemical Anodization ◽  
Oh Radicals ◽  
X Ray Diffraction ◽  
X Ray ◽  
Structure Morphology ◽  
Titanium Thin Films ◽  
Current Densities ◽  
Photogenerated Charge Separation

A novel low-cost synthesis of barium-modified TiO2 nanotube (TNT) arrays was used to obtain an immobilized photocatalyst for degradation of diclofenac. TNT arrays were prepared by electrochemical anodization of titanium thin films deposited on fluorine-doped tin oxide (FTO) coated glass by magnetron sputtering, ensuring transparency and immobilization of the nanotubes. The Ba-modifications were obtained by annealing solutions of Ba(OH)2 spin coated on top of TNT. Three different concentrations of Ba(OH)2 were used (12.5 mM, 25 mM and 50 mM). The crystalline structure, morphology and presence of Ba were characterized by X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy, respectively. Ba-modified TiO2 nanotubes (BTNT) were tested for photocatalytic degradation of diclofenac under UV/Vis radiation and it was proven that all of the Ba-modified samples showed an increase in photocatalytic activity with respect to the unmodified TNTs. The most efficient photocatalyst was the sample prepared with 25 mM Ba(OH)2 which showed 90% diclofenac degradation after 60 min. This result was in agreement with cyclic voltammetry measurements that showed the largest increase in photo-oxidation current densities for the same sample due to the increased generation of •OH radicals obtained by a more efficient photogenerated charge separation.

scholarly journals Photocatalytic activity of TiO2/stevensite nanocomposites for the removal of Orange G from aqueous solutions

Clay Minerals ◽  
2014 ◽  
Vol 49 (3) ◽  
pp. 417-428 ◽  
Author(s):  
L. Bouna ◽  
B. Rhouta ◽  
F. Maury ◽  
A. Jada ◽  
F. Senocq ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Solvothermal Method ◽  
X Ray Diffraction ◽  
Aqueous Dispersions ◽  
X Ray ◽  
Surface Areas ◽  
Surfactant Solutions ◽  
Transmission Electron ◽  
Orange G ◽  
Specific Surface Areas

AbstractTiO2/stevensite nanocomposite photocatalysts were synthesized by a solvothermal method using TiCl3/HCl as reactants and the stevensite clay mineral extract as support. The prepared photocatalyst samples were then characterized using various techniques such as X-ray diffraction (XRD), Infrared spectroscopy (IR) and Transmission Electron Microscopy (TEM). The Points of Zero Charge (PZC) of the various samples were evaluated by titration of the non-modified and the Ti-modified clay aqueous dispersions, with cationic surfactant solutions. The photocatalytic activity of the resulting nanocomposites samples were evaluated for the removal of Orange G (OG) from aqueous solution as a model dye pollutant. The data indicate that the formation of Na+-stevensite by the TiO2 particles leads to TiO2/stevensite nanocomposites having higher specific surface areas and mesopore volumes, and lower PZC values. Further, the photocatalytic activity was greater for the TiO2/stevensite nanocomposites having the greatest Ti amount, as compared to a pure TiO2 sample, and increased with the increase of the TiO2 content in the TiO2/stevensite nanocomposites.

Hydrothermal Synthesis and Visible-Light-Driven Photocatalytic Activity of Allophane – Wakefieldite-(Ce) Composite

2014 ◽  
Vol 896 ◽  
pp. 545-548
Author(s):  
Mirabbos Hojamberdiev ◽  
Yuki Makinose ◽  
Kenichi Katsumata ◽  
Toshihiro Isobe ◽  
Nobuhiro Matsushita ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Hydrothermal Synthesis ◽  
Visible Light ◽  
Gas Phase ◽  
X Ray Diffraction ◽  
Mechanical Mixing ◽  
X Ray ◽  
Surface Areas ◽  
Visible Light Driven ◽  
Gas Molecules

In this study, highly adsorptive mechanically-mixed and as-synthesized allophane–wakefieldite-(Ce) composites were prepared by mechanical mixing and hydrothermal synthesis, respectively. The results from X-ray diffraction and Raman spectroscopy analyses show that the mechanically-mixed composite has higher crystallinity than the as-synthesized composite. The nanoparticles of wakefieldite-(Ce) were homogenously distributed with allophane in the as-synthesized composite. The specific surface areas of the mechanically-mixed and as-synthesized composites are 164 m2/g and 191 m2/g, respectively. The photocatalytic activity of the samples was evaluated for the degradation of acetaldehyde (AcH) gas under visible light. Both composites demonstrated higher photocatalytic activity than individual wakefieldite-(Ce) and allophane because allophane in the composites played an important role in the adsorption of acetaldehyde gas molecules and the mediation between the gas phase and the wakefieldite-(Ce) surface.

The Preparation of Cu2ZnSnSe4 Films by Selenization of the Oxide Precursors

2011 ◽  
Vol 418-420 ◽  
pp. 597-601
Author(s):  
Gui Lin Chen ◽  
Lu Jin ◽  
Wei Feng Liu ◽  
Guo Shun Jiang ◽  
Chang Fei Zhu
Keyword(s):  
Electron Microscopy ◽  
Spin Coating ◽  
Low Cost ◽  
Solvent Free ◽  
Coating Process ◽  
X Ray Diffraction ◽  
Mechanochemical Method ◽  
Spin Coating Process ◽  
X Ray ◽  
Scanning Electron

A low-cost non-vacuum process for fabrication of Cu2ZnSnSe4 (CZTSe) films by solvent-free mechanochemical method and spin-coating process is described. First, highly monodisperse Cu, Zn, Sn oxides nanoparticles are synthesized via a facile, solvent-free route. Second, the oxide particulate precursors are deposited in a thin layer by spin-coating technique. Finally, the dry layers are sintered into CZTSe thin films selenization. Through X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), it is found that near stoichiometric CZTSe films with a micron-sized grains are obtained in our work.

Hydrothermal Method Preparation of Flower-Like Ce-Doped ZnO as an Efficient Photocatalyst

2018 ◽  
Vol 281 ◽  
pp. 872-877
Author(s):  
Jian Ping Ai ◽  
Wei Xiu Liao ◽  
Shan Shan Luo ◽  
Tao Zhou ◽  
Li Hong Cheng ◽  
...  
Keyword(s):  
Photocatalytic Activity ◽  
Hydrothermal Method ◽  
Uv Light ◽  
Low Cost ◽  
Hexagonal Wurtzite Structure ◽  
X Ray Diffraction ◽  
X Ray ◽  
Infrared Spectrometer ◽  
Ft Ir ◽  
Doped Zno

Well-crystalline flower-like Ce-doped ZnO were synthesized by facile and low-cost hydrothermal method. The prepared samples were characterized by a variety of characterization techniques such as X-ray diffraction (XRD), Fourier Transform Infrared Spectrometer (FT-IR), UV-visible spectroscopy, scanning electron microscopy (SEM) combined with energy dispersive X-ray diffraction (EDX), to study the crystal structure, optical properties, surface morphology and chemical composition. It was observed from XRD and FT-IR results that synthesized powder had hexagonal wurtzite structure. The photocatalytic activities of the prepared samples were evaluated by photocatalytic degradation of methyl orange (MO) and Rhodamine B (RhB) under UV light irradiation. The results showed that the Ce-doped ZnO photocatalyst with 0.5% cerium exhibited highest photocatalytic activity compared to other samples. The enhanced photocatalytic activity could be attributed to inhibition of the electron-hole pair’s recombination.

Photocatalytic activity of TiO2 synthesized by anodization and anodic spark deposition

MRS Advances ◽  
2020 ◽  
Vol 5 (61) ◽  
pp. 3141-3152
Author(s):  
Alma C. Chávez-Mejía ◽  
Génesis Villegas-Suárez ◽  
Paloma I. Zaragoza-Sánchez ◽  
Rafael Magaña-López ◽  
Julio C. Morales-Mejía ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Photocatalytic Activity ◽  
Surface Characteristics ◽  
Amorphous Solids ◽  
X Ray Diffraction ◽  
X Ray ◽  
Catalytic Activities ◽  
Anodic Spark Oxidation ◽  
Porous Surfaces ◽  
Scanning Electron

AbstractSeveral photocatalysts, based on titanium dioxide, were synthesized by spark anodization techniques and anodic spark oxidation. Photocatalytic activity was determined by methylene blue oxidation and the catalytic activities of the catalysts were evaluated after 70 hours of reaction. Scanning Electron Microscopy and X Ray Diffraction analysis were used to characterize the catalysts. The photocatalyst prepared with a solution of sulfuric acid and 100 V presented the best performance in terms of oxidation of the dye (62%). The electric potential during the synthesis (10 V, low potential; 100 V, high potential) affected the surface characteristics: under low potential, catalyst presented smooth and homogeneous surfaces with spots (high TiO2 concentration) of amorphous solids; under low potential, catalyst presented porous surfaces with crystalline solids homogeneously distributed.

scholarly journals Multidimensional Ln-Aminophthalate Photoluminescent Coordination Polymers

Materials ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1786
Author(s):  
Carla Queirós ◽  
Chen Sun ◽  
Ana M. G. Silva ◽  
Baltazar de Castro ◽  
Juan Cabanillas-Gonzalez ◽  
...  
Keyword(s):  
Water Content ◽  
Coordination Polymers ◽  
Metal Ion ◽  
Low Cost ◽  
Microwave Assisted Synthesis ◽  
X Ray Diffraction ◽  
X Ray ◽  
Wide Range ◽  
Ft Ir ◽  
Ft Ir Spectroscopy

The development of straightforward reproducible methods for the preparation of new photoluminescent coordination polymers (CPs) is an important goal in luminescence and chemical sensing fields. Isophthalic acid derivatives have been reported for a wide range of applications, and in addition to their relatively low cost, have encouraged its use in the preparation of novel lanthanide-based coordination polymers (LnCPs). Considering that the photoluminescent properties of these CPs are highly dependent on the existence of water molecules in the crystal structure, our research efforts are now focused on the preparation of CP with the lowest water content possible, while considering a green chemistry approach. One- and two-dimensional (1D and 2D) LnCPs were prepared from 5-aminoisophthalic acid and Sm3+/Tb3+ using hydrothermal and/or microwave-assisted synthesis. The unprecedented LnCPs were characterized by single-crystal X-ray diffraction (SCRXD), powder X-ray diffraction (PXRD), Fourier transform infrared (FT-IR) spectroscopy and scanning electron microscopy (SEM), and their photoluminescence (PL) properties were studied in the solid state, at room temperature, using the CPs as powders and encapsulated in poly(methyl methacrylate (PMMA) films, envisaging the potential preparation of devices for sensing. The materials revealed interesting PL properties that depend on the dimensionality, metal ion, co-ligand used and water content.

scholarly journals Mechanochemical treatment of Serbian kaolin clay to obtain high reactive pozzolana

2013 ◽  
Vol 78 (4) ◽  
pp. 579-590 ◽  
Author(s):  
Aleksandra Mitrovic ◽  
Miodrag Zdujic
Keyword(s):  
Hardened Steel ◽  
Pozzolanic Activity ◽  
Mechanochemical Treatment ◽  
Kaolin Clay ◽  
X Ray Diffraction ◽  
Scanning Calorimetry ◽  
X Ray ◽  
Milling Parameters ◽  
Milling Medium ◽  
The Given

Mechanochemical treatment of Serbian kaolin clay was carried out in a planetary ball mill using two different milling media, hardened steel or zirconia vials and balls. The samples obtained with various milling times were characterized by the particle size laser diffraction (PSLD), X-ray diffraction (XRD), differential scanning calorimetry/thermogravimetry (DTA/TGA) and Fourier-transform infrared (FTIR) analyses. Mechanochemical treatment induced amorphization of the kaolinite phase accompanied by dehydroxylation. It was found that for the given milling parameters, amorphization mainly took place in the milling period up to 15 min, and was completed after about 30 min of milling for both milling media used. The pozzolanic activities were determined by the Chapelle method. Milling in the hardened steel milling medium had no significant influence on pozzolanic activity, even though there was accumulated iron contamination. For both milling media, pozzolanic activity of 0.79 was obtained for the samples milled for 15 min and it remained almost unchanged with prolonged milling. The determined pozzolanic activity values are close to these of commercial metakaolinite or metakaolinite obtained by the calcination of the same clay, therefore, indicating possibility for obtaining high reactive pozzolana by mechanochemical treatment of Serbian kaoline clay.

Photocatalytic Activity of Fe-Doped ZnO/Montmorillonite Nanocomposite for Degradation of Malachite Green

2015 ◽  
Vol 827 ◽  
pp. 19-24 ◽  
Author(s):  
Nur Afifah ◽  
Nadia Febiana Djaja ◽  
Rosari Saleh
Keyword(s):  
Photocatalytic Activity ◽  
Malachite Green ◽  
Organic Dyes ◽  
Uv Light ◽  
Precipitation Method ◽  
X Ray Diffraction ◽  
X Ray ◽  
Spin Resonance ◽  
Doped Zno ◽  
Co Precipitation

In this study, the photocatalytic activity of pure Fe- doped ZnO and Fe- doped ZnO/Montmorillonite nanocomposite has been investigated for the degradation of malachite green under UV light irradiation. Both photocatalysts were synthesized using co-precipitation method and characterized by X-ray diffraction, energy dispersive X-ray spectroscopy, Fourier-transform infrared absorption, and electron spin resonance. The results showed that the photocatalytic efficiency is better in the presence of montmorillonite compared to pure Fe- doped ZnO. To detect the possible reactive species involved in degradation of organic dyes control experiments with introducing scavengers into the solution of organic dyes were carried out. It is found that electron plays an important role in the degradation of malachite green.

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