UV-Light Absorption Properties of Cr-Doped Polyethyleneglycol (PEG)/γ-Glycidoxypropyltrimethoxysilane (GPTMS)/Chelated-Titanium Coating Materials Prepared by the Sol–Gel Process

In this work two different hydrosols were used to impregnate a commercially available cotton fabric with anatase nanoparticles to give it photocatalytic activity. To increase the activity, different pre-treatment methods were applied. The nanoparticle size was determined using dynamic light scattering and x-ray diffraction and the fabrics were examined using scanning electron microscopy. Photocatalytic activity was measured using the degradation of methyl-orange while irradiating the samples with UV light. The synthesis method allowed to produce anatase with an average particle size of 32 to 37 nm depending on the synthesis method used.

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Indium-Sensitized UV Photocatalysts Made from Alkali Titanate Microfibers

Materials Science Forum ◽

10.4028/www.scientific.net/msf.620-622.651 ◽

2009 ◽

Vol 620-622 ◽

pp. 651-654

Author(s):

Leticia M. Torres-Martínez ◽

Cecilia Sánchez-Trinidad ◽

Vicente Rodríguez-González ◽

Ricardo Gómez

Keyword(s):

Heat Treatment ◽

Annealing Time ◽

Uv Light ◽

Sol Gel ◽

Dichlorophenoxyacetic Acid ◽

Sem Images ◽

Uv Light Irradiation ◽

Heat Treated ◽

Munk Function ◽

Sol Gel Process

Indium-alkali microfibers doped ceramic were prepared by the sol-gel process. The gels preparation samples, were heat treated at 700°C for different length of time. The products were characterized by means of XRD, SEM-EDS and UV–Vis-DRS. The XRD showed the formation of the Na2Ti6O13 phase whose crystallinity depends on the annealing time. The band gap calculated from the UV–Vis Kubelka-Munk function shows very similar values (3.53-3.55 eV). The SEM images of the indium-alkali titanates show microfiber clumps morphologies of about 5 µm, and the EDS spectra show that In2O3 is on the Na2Ti6O13 surface. The results of the evaluation of the In-Na2Ti6O13 semiconductors in the 2, 4-dichlorophenoxyacetic acid (2, 4-D) photodecomposition under UV light irradiation, show that the photoactivity depends on the time of heat treatment of the samples.

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Synthesis and Characterization of SiO2@Y2MoO6:Eu3+ Core–Shell Structured Spherical Phosphors by Sol–Gel Process

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2016.11862 ◽

2016 ◽

Vol 16 (4) ◽

pp. 3914-3920 ◽

Cited By ~ 1

Author(s):

G. Z Li ◽

F. H Liu ◽

Z. S Chu ◽

D. M Wu ◽

L. B Yang ◽

...

Keyword(s):

Electron Microscopy ◽

Annealing Temperature ◽

Uv Light ◽

Sol Gel ◽

Spherical Shape ◽

Core Shell ◽

X Ray ◽

Transmission Electron ◽

Sol Gel Process ◽

Average Size

SiO2@Y2MoO6:Eu3+ core–shell phosphors were prepared by the sol–gel process. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectra (EDS), transmission electron microscopy (TEM), photoluminescence (PL) spectra as well as kinetic decays were used to characterize the resulting SiO2@Y2MoO6:Eu3+ core–shell phosphors. The XRD results demonstrated that the Y2MoO6:Eu3+ layers on the SiO2 spheres crystallized after being annealed at 700 °C and the crystallinity increased with raising the annealing temperature. The obtained core–shell phosphors have spherical shape with narrow size distribution (average size ca. 640 nm), non-agglomeration, and smooth surface. The thickness of the Y2MoO6:Eu3+ shells on the SiO2 cores could be easily tailored by varying the number of deposition cycles (70 nm for four deposition cycles). The Eu3+ shows a strong PL emission (dominated by 5D0–7F2 red emission at 614 nm) under the excitation of 347 nm UV light. The PL intensity of Eu3+ increases with increasing the annealing temperature and the number of coating cycles.

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Photocatalytic Reduction of AuCl4- by Fe3O4/SiO2/TiO2 Nanoparticles

Global NEST Journal ◽

10.30955/gnj.003262 ◽

2020 ◽

Keyword(s):

Tio2 Nanoparticles ◽

Uv Light ◽

Electronic Waste ◽

Sol Gel ◽

Photocatalytic Reduction ◽

Light Illumination ◽

Magnetite Fe3o4 ◽

Sol Gel Process ◽

Competitive Reduction ◽

Closed Reactor

<p>Metallurgy and recovery of gold in electronic waste sometimes involve the reduction of tetrachloroaurate ion (AuCl4-) to elemental gold form. Currently, for the reduction of tetrachloroaurate ion, people use reducing agents such as hydroquinone and sodium borohydride. Photocatalysts of Fe3O4/SiO2/TiO2 nanoparticles were prepared and tested for the reduction of tetrachloroaurate ion under UV light illumination. The magnetite (Fe3O4) nanoparticle was first prepared by coprecipitation and sonication, followed by SiO2 and TiO2 coatings via the sol-gel process and calcination. The products were confirmed by XRD and TEM. The photocatalytic reduction of tetrachloroaurate ion was performed in a closed reactor equipped with a UV light source. The results indicated that Fe3O4/SiO2/TiO2 nanoparticles were successfully prepared, which retained good magnetic and photocatalytic properties. The photocatalytic reaction is best performed at a pH of 5 under UV irradiation for 2 h, which is capable of reducing 96% of the tetrachloroaurate present in the mixture. The co-presence of Ni2+ and Cu2+ ions in the solution leads to a decrease in yield due to competitive reduction and adsorption. The photocatalyst is recoverable by the use of a magnetic bar and may find application for gold recovery and metallurgy.</p>

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Visible-Light Driven LaNiO3 Nanosized Photocatalysts Prepared by a Sol-Gel Process

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.279.83 ◽

2011 ◽

Vol 279 ◽

pp. 83-87 ◽

Cited By ~ 7

Author(s):

Pei Song Tang ◽

He Sun ◽

Feng Cao ◽

Jin Tian Yang ◽

Sheng Liang Ni ◽

...

Keyword(s):

Photocatalytic Activity ◽

Methyl Orange ◽

Visible Light ◽

Light Absorption ◽

Diffuse Reflectance Spectroscopy ◽

Sol Gel ◽

High Photocatalytic Activity ◽

Visible Light Absorption ◽

Average Grain Size ◽

Sol Gel Process

The LaNiO3 nanoparticles were prepared by a sol-gel process. The LaNiO3 nanoparticles were characterized by powder X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV-Vis diffuse reflectance spectroscopy (DRS). XRD and SEM demonstrate the successful synthesis of single phase perovskite LaNiO3 and an average grain size of 80 nm in diameter. It was found that the as-prepared LaNiO3 shows strong visible-light absorption with absorption onset of 545 nm, indicating a narrow optical band gap of 2.28 eV. Consequently, LaNiO3 nanoparticles show high visible-light photocatalytic activity for decomposition of methyl orange in comparison with the commercial Degussa P25. The photocatalytic experiment shows the high photocatalytic activity for the decomposition of methyl orange under visible-light irradiation, which is attributed to the strong visible-light absorption.

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Moisture absorption properties of hardwood veneers modified by a sol-gel process

Holzforschung ◽

10.1515/hf-2016-0151 ◽

2017 ◽

Vol 71 (7-8) ◽

pp. 645-648 ◽

Cited By ~ 3

Author(s):

Edgars Kirilovs ◽

Silvija Kukle ◽

Janis Gravitis ◽

Hans-Jörg Gusovius

Keyword(s):

Thin Films ◽

Moisture Absorption ◽

Sol Gel ◽

Organic Thin Films ◽

Protective Agent ◽

Moisture Uptake ◽

Absorption Properties ◽

Organic Light ◽

Sol Gel Process

Abstract A new invisible nanolevel coating has been developed based on the sol-gel process for veneer finishes. The sol synthesis and its application as a protective agent is described. It could be demonstrated that a combination of organic light stabilizers and sol-gel deposits is feasible and that the resulting hybrid inorganic-organic thin films decrease moisture uptake of hardwood veneers.

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UV-absorption and thermal properties of Pb-doped glymo/damo-derived coating materials prepared by sol–gel process

Journal of Materials Science Letters ◽

10.1007/s10855-005-4563-z ◽

2005 ◽

Author(s):

F. Sayilkan ◽

M. AsİltÜrk ◽

M. G. İÇduygu ◽

H. Sayilkan

Keyword(s):

Thermal Properties ◽

Sol Gel ◽

Uv Absorption ◽

Coating Materials ◽

Sol Gel Process

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Structural and Ferroelectric Properties of Bi4-xNixTi3O12 Thin Films by Sol-Gel Process

MRS Proceedings ◽

10.1557/proc-0966-t07-10 ◽

2006 ◽

Vol 966 ◽

Author(s):

Ricardo Melgarejo ◽

Maharaj S Tomar ◽

Rahul Singhal ◽

Ram S Katiyar

Keyword(s):

Thin Films ◽

Ferroelectric Properties ◽

Sol Gel ◽

Low Frequency ◽

X Ray Diffraction ◽

Coating Materials ◽

Low Field ◽

Sol Gel Process ◽

Raman Modes ◽

Ferroelectric Memories

ABSTRACTNickel-substituted Bi4Ti3O12 (i.e., Bi4-xNixTi3O12) were synthesized by sol-gel process for different compositions. Thin films were deposited on Pt (i.e., Pt/TiO2/SiO2/Si) substrate by spin coating. Materials were characterized by x-ray diffraction and Raman spectroscopy. This study indicates that the material makes a solid solution for the compositions: x = 0.00, 0.05, 0.10, 0.15, 0.20, and 0.30, where a Ni ion replaces the Bi site. The prominent effect of Ni substitution was observed in low-frequency Raman modes. Sol-gel derived thin films of Bi4-xNixTi3O12 on a Pt substrate and post annealed at 700°C were tested for ferroelectric response which showed high remnant polarization (Pr = 22 μC/cm2 for x = 0.15). The leakage current (less then 10−7 A/cm2) at low field was observed in the film with composition x = 0.15 .The polarization of the BNiT (x = 0.15) film decreased to 83% of the initial value after 1×109 switching cycles These results indicate the potential application of Ni substituted bismuth titanate films in non-volatile ferroelectric memories.

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