Morphological Analysis of Ag Doped on TiO2/Ti Prepared via Anodizing and Thermal Oxidation Methods

In this work, we present the morphology analysis of TiO2/Ti prepared via anodizing and thermal oxidation (TO) methods and doped by Ag-TiO2 sol-gel nanocomposites through liquid phase deposition (LPD) technique. The comparative morphology of both semiconductors has been observed to inform the catalysis preparation for better morphology structures to the photocatalytic performance. Based on these results, we report that the TiO2/Ti prepared via anodizing method exhibits TiO2 nanotubes arrays (TNTAs) formed like honeycomb structures, while the TiO2/Ti TO (TTO) has diverse size structures. The neat arrangement of TNTAs has a larger surface area and pore volume than TTO structures, which can expose more adsorption and reaction sites, resulting in higher catalytic activity. Uniquely, both semiconductors, after coated by Ag-TiO2 sol-gel, show lamellar sediments covering the surface of TNTAs and TTO. We believe that the anodizing method is a good ability for photocatalysis compared with TTO in terms of small surface area and nanosize structures.

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TiO2 composite films on different substrates with enhanced visible light photocatalytic performance

Functional Materials Letters ◽

10.1142/s1793604720510376 ◽

2020 ◽

Vol 13 (07) ◽

pp. 2051037

Author(s):

Ke Han ◽

Guobao Li ◽

Fang Li ◽

Mingming Yao

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Specific Surface ◽

Surface Area ◽

Specific Surface Area ◽

Photocatalytic Performance ◽

Sol Gel ◽

Composite Films ◽

Methyl Green ◽

Photogenerated Electrons

For the sake of improving the photocatalytic performance of TiO2, we prepared the B/Ag/Fe tridoped TiO2 films on common glass and stone substrates by the sol–gel method. In this work, the optical absorption, recombination of photogenerated electrons (e−) and holes (h[Formula: see text]), crystal types, thermal stability, composition, specific surface area and photocatalytic activity of the modified TiO2 films were investigated. The results indicated that B/Ag/Fe tridoping not only enhanced the absorption of visible light by TiO2, but inhibited the recombination of electron–hole (e−/h[Formula: see text]) pairs. The tridoping also promoted the formation of anatase and prevented the transformation of anatase to rutile at high temperature. The composite TiO2 has a large specific surface area, about three times that of pure TiO2. The photocatalytic activity of the TiO2 films were evaluated by methyl green (MG) and formaldehyde degradation. In all samples, the B/Ag/Fe tridoped TiO2 film exhibited the highest degradation rate of MG under both ultraviolet and visible light irradiation. The improvement of photocatalytic performance of TiO2 films is due to the synergistic effect of the B/Ag/Fe tridoping, which enhances the absorption of visible light and prolongs the lifetime of e−/h[Formula: see text] pairs and facilitates transfer of interface charge.

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Effects of Calcination on Sol-gel Synthesis of Hollow Spherical 8%B-TiO2 for Photocatalytic Degradation of RBR X-3B -Characterization and Activity

Current Nanoscience ◽

10.2174/1573413714666180717112803 ◽

2019 ◽

Vol 15 (3) ◽

pp. 289-295 ◽

Cited By ~ 2

Author(s):

Lili Yang ◽

Yao Zhao ◽

Jing Li ◽

Yanwen Zhou ◽

Xuan Xiao ◽

...

Keyword(s):

Photocatalytic Degradation ◽

Surface Area ◽

Calcination Temperature ◽

Sol Gel ◽

Degradation Process ◽

Maximum Activity ◽

Bet Surface Area ◽

Tetrabutyl Titanate ◽

Tio2 Sample ◽

Small Surface

Background: TiO2-based materials can be utilized in both polluted air and wastewater treatments. Ion doping is the most applied modification method, and many kinds of metal ions and nonmetal ions are doped into a TiO2 crystalline skeleton. The hollow spherical photocatalyst can both easily suspend in wastewater under aeration and settle down after treatment to release the water. Methods: The hollow spherical B-TiO2 photocatalyst was prepared by a sol-gel method. Tetrabutyl titanate and tributyl borate were used as the titanium and boron sources. The materials were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), infrared spectrum (FTIR), and N2 adsorption-desorption techniques. Results: The 8%B-TiO2 material is composed of anatase TiO2 when the calcination temperature is below 600°C. The graphical template is burnt out during calcination to leave a hole in the spherical 8%B-TiO2. The BET surface area of the materials declines from 53.2 m2/g at 400°C to 10.6 m2/g at 700°C. High-temperature thermal treatment results in the small surface area and large pore size. The activity of the 8%B-TiO2 materials was studied on adsorption and photocatalytic degradation of RBR X-3B dye. The 8%B-TiO2 sample prepared at 600°C has the maximum activity on RBR X-3B degradation. After five cycles, decoloration efficiency on the 8%B-TiO2 decreases from 100% in the first cycle to 80% in the fifth cycle. Conclusion: Photocatalytic activity of the hollow spherical material depends on calcination temperature with the optimum activity on the sample obtained at 600°C. The hollow spherical 8%B-TiO2 has satisfactory performance for recycling. Photocatalytic degradation of RBR X-3B can be proven by the UV-Vis spectra during the degradation process.

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The Influence of TiO2 Photoanode Morphology for Scattering Enhanced Properties of Dye-Sensitized Solar Cell

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.667.425 ◽

2013 ◽

Vol 667 ◽

pp. 425-434 ◽

Cited By ~ 2

Author(s):

Mohd Hanapiah Abdullah ◽

Ismail Lyly Nyl ◽

Mohamed Zahidi Musa ◽

Mohamad Rusop Mahmood

Keyword(s):

Pore Size ◽

Surface Area ◽

High Surface ◽

Sol Gel ◽

High Surface Area ◽

Tio2 Electrode ◽

Pore Size Distributions ◽

Tio2 Sol ◽

Micron Size ◽

Enhanced Properties

Effect of PEG on the TiO2 electrode morphology for scattering enhanced properties of the modified paste containing TiO2 sol-gel mixed with Degussa P-25 were investigated. The high surface area of the scattering centres in this study were formed by using nano size particles ascribed from TiO2 sol-gel while the sub-micron size particles were utilized from the reaction of PEG on the Degussa P-25 particles. The pore size distributions were tailored by varying the PEG content in the fabricated electrodes. Higher surface area with adequate pore size of P30 electrode has contributed to higher JSC and efficiency (η) of 11.35450 mA/cm2 and 2.479624 %, respectively. Photocurrent action spectra of IPCE of the DSSC exhibit the maximum of 42 % at 550 nm correspond to the P30 TiO2 electrode. Overall results suggest that the incorporation of TiO2 sol-gel component mixed with TiO2 paste derived from commercially available nanopowder could enhance surface area as well as serves for better light scattering effect, while PEG addition creates adequate pore size distribution to maximize the dye adsorbed on the TiO2 electrode.

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Effect of the Preparation Method (Sol-Gel or Hydrothermal) and Conditions on the TiO2 Properties and Activity for Propene Oxidation

Materials ◽

10.3390/ma11112227 ◽

2018 ◽

Vol 11 (11) ◽

pp. 2227 ◽

Cited By ~ 9

Author(s):

Laura Cano-Casanova ◽

Ana Amorós-Pérez ◽

María Lillo-Ródenas ◽

María Román-Martínez

Keyword(s):

Heat Treatment ◽

Surface Area ◽

Photocatalytic Performance ◽

Sol Gel ◽

Propene Oxidation ◽

Vis Spectroscopy ◽

Post Synthesis ◽

Adsorption Desorption ◽

Hydrolysis Of ◽

Selection Of

Since the two most commonly used methods for TiO2 preparation are sol-gel (SG) and hydrothermal (HT) synthesis, this study attempts to compare both methods in order to determine which one is the most suitable to prepare photocatalysts for propene oxidation. In addition, this work studies how the concentration of the HCl used for hydrolysis of the TiO2 precursor affects the properties of the obtained materials. Also, the effect of avoiding the post-synthesis heat-treatment in a selection of samples is investigated. The photocatalysts are characterized by XRD, N2 adsorption-desorption isotherms and UV-vis spectroscopy, and the study tries to correlate the properties with the photocatalytic performance of the prepared TiO2 samples in propene oxidation. TiO2 materials with high crystallinity, between 67% and 81%, and surface area (up to 134 m2/g) have been obtained both by SG and HT methods. In general, the surface area and pore volume of the TiO2-HT samples are larger than those of TiO2-SG ones. The TiO2-HT catalysts are, in general, more active than TiO2-SG materials or P25 in the photo-oxidation of propene. The effect of HCl presence during the TiO2 synthesis and of the post synthesis heat treatment are much more marked in the case of the SG materials.

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Preparation and Application of Mesoporous Nanotitania Photocatalysts Using Different Templates and pH Media

International Journal of Photoenergy ◽

10.1155/2014/687597 ◽

2014 ◽

Vol 2014 ◽

pp. 1-11 ◽

Cited By ~ 8

Author(s):

S. M. Abdel-Azim ◽

A. K. Aboul-Gheit ◽

S. M. Ahmed ◽

D. S. El-Desouki ◽

M. S. A. Abdel-Mottaleb

Keyword(s):

Phase Transformation ◽

Surface Area ◽

Photocatalytic Performance ◽

Irradiation Time ◽

Sol Gel ◽

Nonylphenol Ethoxylate ◽

Naphthalene Degradation ◽

Low Concentrations ◽

Surfactant Phase ◽

Visible Irradiation

Mesoporous nanotitania photocatalysts were prepared by sol-gel method in acidic or basic media. Three types of surfactants, namely, cetyltrimethylammonium bromide, sodium dodecylbenzenesulfonate, and nonylphenol ethoxylate, were used as templating agents. The effects of surfactant type and pH on the morphology, particle size, surface area, pore-size distribution, UV-Vis absorbance, and TiO2phase transformation were traced by SEM, TEM, BET, and XRD. In absence of surfactants, XRD revealed 54.5% anatase at pH 3-4 and 97.0% at pH 7–9. In presence of surfactant, phase transformation of anatase has been significantly inhibited such that anatase amounts to 82–100% in acidic media. In basic media, the brookite phase appeared in low concentrations (8–15%) while rutile totally disappeared. The photocatalytic performance of the synthesized catalysts was tested via naphthalene degradation, which exhibited high activity in visible irradiation (>400 nm). The data obtained indicate that the surface area and pore volume of the current catalysts are the most effective factors for photocatalytic performance. Nevertheless, at the low pH (acidic) range, the CTAB templated catalyst gave the highest surface area (86.7 cm3/g), which is mainly assigned to acquiring the highest photocatalytic degradation of naphthalene (97% after 4 h irradiation time).

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Thickness controlled SiO2/TiO2 sol-gel coating by spraying

Open Ceramics ◽

10.1016/j.oceram.2021.100121 ◽

2021 ◽

pp. 100121

Author(s):

M. Jacobs ◽

Y. De Vos ◽

V. Middelkoop

Keyword(s):

Sol Gel ◽

Tio2 Sol

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Optical, electrical and mechanical properties of TiN thin film obtained from a TiO2 sol-gel coating and rapid thermal nitridation

Surface and Coatings Technology ◽

10.1016/j.surfcoat.2021.127089 ◽

2021 ◽

pp. 127089

Author(s):

Arnaud Valour ◽

Maria Alejandra Usuga Higuita ◽

Gaylord Guillonneau ◽

Nicolas Crespo-Monteiro ◽

Damien Jamon ◽

...

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Sol Gel ◽

Tio2 Sol ◽

Thermal Nitridation

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A simple tactic synthesis of hollow porous graphitic carbon nitride with significantly enriched photocatalytic performance

Chemical Communications ◽

10.1039/d1cc02355a ◽

2021 ◽

Author(s):

Vellaichamy Balakumar ◽

Manivannan Ramalingam ◽

Chitiphon Chuaicham ◽

KARTHIKEYAN SEKAR ◽

K. Sasaki

Keyword(s):

Crystal Structure ◽

Surface Area ◽

Carbon Nitride ◽

Photocatalytic Performance ◽

Porous Graphitic Carbon ◽

Graphitic Carbon ◽

Graphitic Carbon Nitride ◽

Modified Surface

Hollow porous graphitic carbon nitride (porous CN) was synthesized via a simple tactic method, and the resulting porous CN showed an effectively modified surface area, crystal structure and enhanced photocatalytic...

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