Thermal Behavior ofTiO2-xNxNanostructured Powder

International Journal of Photoenergy ◽

10.1155/2008/267345 ◽

2008 ◽

Vol 2008 ◽

pp. 1-7 ◽

Cited By ~ 1

Author(s):

Vladimír Balek ◽

Jan Šubrt ◽

Hiroshi Irie ◽

Kazuhito Hashimoto

Keyword(s):

Thermal Behavior ◽

Nitrogen Adsorption ◽

Gaseous Ammonia ◽

Subsurface Structure ◽

Titania Powder ◽

Anatase Titania ◽

Porous Titania ◽

Diffusion Paths ◽

Structure Irregularities ◽

Doped Titania

Diffusion structural analysis (DSA), based on the measurement of the release of radon previously incorporated into the samples, was used to characterize thermal behavior of N-doped titania powder prepared by heat treatment of anatase in gaseous ammonia at575∘Cand the referenceTiO2powder prepared from the ST-01 anatase titania powder (Ishihara Ltd., Japan). The results of DSA, surface area and porosity measurements by nitrogen adsorption, SEM micrographs, XPS, and XRD are presented and discussed. The results of DSA are in agreement with the results of other methods and indicated the annealing of the subsurface structure irregularities of the samples. Transport properties of the samples were determined from the mobility of radon atoms released on sample heating in air. The decrease of radon permeability in the porous titania powders in the temperature range 850–1000∘Cdue to annealing of the subsurface structure irregularities, that served as radon diffusion paths in the samples, was evaluated from the DSA results.

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The influence of the nature and textural properties of different supports on the thermal behavior of Keggin type heteropolyacids

Journal of the Serbian Chemical Society ◽

10.2298/jsc0603235p ◽

2006 ◽

Vol 71 (3) ◽

pp. 235-249 ◽

Cited By ~ 23

Author(s):

Alexandru Popa ◽

Viorel Sasca ◽

Mircea Stefanescu ◽

Erne Kis ◽

Radmila Marinkovic-Neducin

Keyword(s):

Thermal Stability ◽

Thermal Decomposition ◽

Thermal Behavior ◽

Solid Phase ◽

Textural Properties ◽

Nitrogen Adsorption ◽

Active Phase ◽

Support Surface ◽

Sem Images ◽

The Stability

In order to obtain highly dispersed heteropolyacids (HPAs) species, H3PMo12O40 and H4PVMo11O40 were supported on various supports: silica (Aerosil - Degussa and Romsil types) and TiO2. The structure and thermal decomposition of supported and unsupported HPAs were followed by different techniques (TGA-DTA, FTIR, XRD, low temperature nitrogen adsorption, scanning electron microscopy). All the supported HPAs were prepared by impregnation using the incipient wetness technique with a 1:1 mixture of water-ethanol. Samples were prepared with different concentrations to examine the effect of loading on the thermal behavior of the supported acid catalysts. The thermal stability was evaluated with reference to the bulk solid acids and mechanical mixtures. After deposition on silica types supports, an important decrease in thermal stability was observed on the Romsil types and a small decrease on the Aerosil type. The stability of the heteropolyacids supported on titania increased due to an anion-support interaction, as the thermal decomposition proceeded in two steps. The structure of the HPAs was not totally destroyed at 450 ?C as some IR bands were still preserved. A relatively uniform distribution of HPAs on the support surface was observed for all compositions of the active phase. No separate crystallites of solid phase HPAs were found in the SEM images.

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Synthesis of Mesoporous V-TiO2 with Different Surfactants: The Effect of Surfactant Type on Photocatalytic Properties

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.702.56 ◽

2013 ◽

Vol 702 ◽

pp. 56-61 ◽

Cited By ~ 4

Author(s):

Rahmatollah Rahimi ◽

Masoumeh Mahjoub Moghaddas ◽

Solmaz Zargari ◽

Rahim Rahimi

Keyword(s):

Photocatalytic Activity ◽

Gemini Surfactant ◽

Nitrogen Adsorption ◽

Pluronic F127 ◽

Pluronic P123 ◽

Visible Light Driven ◽

Ft Ir ◽

Doped Titania ◽

Adsorption Desorption ◽

First Time

Mesoporous vanadium doped titania (V-TiO2) photocatalyst was synthesized with the use of a new surfactant (Gemini) for the first time. In order to investigate the surfactant effect on the photocatalytic activity of catalysts, different surfactants containing Gemini, pluronic F127, pluronic P123, CTAB, Hexadecylamine and PEG 6000 were used in the preparation of mesoporous V-TiO2photocatalyst as a templating agent. The catalysts were characterized by FT-IR, XRD, SEM, EDX, nitrogen adsorption-desorption isotherm, and DRS. The nanosized V-TiO2 with Gemini surfactant (V-TiO2(G)) exhibited the highest visible light driven photocatalytic efficiency for degrading MO dye. The results showed that the surfactant type played an important role on the structure and photocatalytic activity of the samples.

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Vanadium oxides doped porous titania photocatalysts for phenol photodegradation

Malaysian Journal of Fundamental and Applied Sciences ◽

10.11113/mjfas.v12n1.407 ◽

2016 ◽

Vol 12 (1) ◽

Cited By ~ 1

Author(s):

Siew Ling Lee ◽

Swee Por Khaw ◽

Yee Khai Ooi

Keyword(s):

Anatase Phase ◽

Sol Gel ◽

Phenol Degradation ◽

Nitrogen Adsorption ◽

Band Gap Energy ◽

Vanadium Oxides ◽

Ammonium Bromide ◽

Porous Titania ◽

Cetyltrimethyl Ammonium ◽

Adsorption Desorption

Vanadium oxides (1 - 5 wt%) doped porous TiO2 using tetrabutyltitanate and cetyltrimethyl ammonium bromide as Ti precursor and template, respectively was successfully synthesized via sol-gel method. All the samples crystallined in anatase phase as indicated by X-ray diffraction analysis. The results of diffused reflectance UV-visible spectroscopy analysis showed that the band gap energy of TiO2 reduced from 3.02 to 2.72 eV after introduction of 5 wt% V. The nitrogen adsorption-desorption analysis revealed that the surface area of samples increased with the amount of V dopant. These materials contained of disorder mesopores with particle size ranged 5 – 56 nm. Amongst, sample 4V-TBT-p-TiO2 recorded the highest percentage of phenol degradation (62.2%) under visible light irradiation

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Photocatalytic properties of Ru-doped titania prepared by homogeneous hydrolysis

Open Chemistry ◽

10.2478/s11532-009-0019-x ◽

2009 ◽

Vol 7 (2) ◽

pp. 259-266 ◽

Cited By ~ 6

Author(s):

Vendula Houšková ◽

Václav Štengl ◽

Snejana Bakardjieva ◽

Nataliya Murafa ◽

Václav Tyrpekl

Keyword(s):

Electron Microscopy ◽

Ruthenium Oxide ◽

Nitrogen Adsorption ◽

Photocatalytic Decomposition ◽

X Ray Diffraction ◽

Selected Area Electron Diffraction ◽

Transmission Electron ◽

Doped Titania ◽

Adsorption Desorption ◽

Hydrolysis Of

AbstractNanocrystalline titania particles doped with ruthenium oxide have been prepared by the homogenous hydrolysis of TiOSO4 in aqueous solutions in the presence of urea. The synthesized particles were characterized by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), High Resolution Transmission Electron Microscopy (HRTEM), Selected Area Electron Diffraction (SAED) and Nitrogen adsorption-desorption was used for surface area (BET) and porosity determination (BJH). The photocatalytic activity of the Ru-doped titania samples were determined by photocatalytic decomposition of Orange II dye in an aqueous slurry during irradiation at 365 nm and 400 nm wavelengths.

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Synthesis of bimodally porous titania powders by hydrolysis of titanium tetraisopropoxide

Journal of Materials Research ◽

10.1557/jmr.2000.0334 ◽

2000 ◽

Vol 15 (11) ◽

pp. 2322-2329 ◽

Cited By ~ 28

Author(s):

Ki Chang Song ◽

Sotiris E. Pratsinis

Keyword(s):

Phase Composition ◽

Calcination Temperature ◽

Water Concentration ◽

Nitrogen Adsorption ◽

Molar Ratio ◽

Titanium Tetraisopropoxide ◽

X Ray Diffraction ◽

Porous Titania ◽

Nitrogen Adsorption Isotherms ◽

Hydrolysis Of

Bimodally porous titania powders with controlled phase composition and porosity were made by hydrolysis of titanium tetraisopropoxide (TTIP) and calcination. The extent of calcination was followed by thermogravimetric differential thermal analysis and Fourier transform infrared spectroscopy. The specific surface area (SSA) of the powders ranged from 10 to 500 m2/g as determined by nitrogen adsorption. The SSA increased by decreasing either the water concentration during hydrolysis or the calcination temperature. The pore size distribution was bimodal with fine intraparticle pore diameters at 1–6 nm and larger interparticle pore diameters at 30–120 nm as determined by nitrogen adsorption isotherms. The particle phase composition as determined by x-ray diffraction ranged from amorphous to crystalline anatase and rutile largely proportional to the calcination temperature and to a lesser extent on the initial H2O/TTIP molar ratio.

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Synthesis and Electrochemical Properties of Porous Titania Fabricated from Nanosheets

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.566.111 ◽

2013 ◽

Vol 566 ◽

pp. 111-114 ◽

Cited By ~ 2

Author(s):

Mitsumasa Sakao ◽

Norihito Kijima ◽

Masashi Yoshinaga ◽

Junji Akimoto ◽

Takeshi Okutani

Keyword(s):

Electrochemical Properties ◽

Spray Drying ◽

Active Material ◽

Nitrogen Adsorption ◽

Mesoporous Structure ◽

Lithium Insertion ◽

Lithium Cell ◽

Porous Titania ◽

Desorption Isotherms ◽

Adsorption Desorption

A porous titania was synthesized by spray-drying of titania nanosheets exfoliated by (C4H9)4NOH. Nitrogen adsorption-desorption isotherms showed that the porous titania has a mesoporous structure composed of slit-shaped pores. The porous titania acted as a rechargeable active material in a liquid organic electrolyte lithium cell. An initial lithium insertion capacity was about 150 mAh/g (cut-off voltage of 1.0 V), which approximately correspond to the composition of Li0.45TiO2.

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The Efficiency of Pt-Doped Titania Pillared Clay Membranes for the Treatment of Real Textile Wastewater: A Case Study

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.843.116 ◽

2020 ◽

Vol 843 ◽

pp. 116-121

Author(s):

Tanushree Choudhury

Keyword(s):

Textile Wastewater ◽

Pillared Clay ◽

X Ray Diffraction ◽

Solution Ph ◽

X Ray ◽

Filtration Cycle ◽

Anatase Titania ◽

Ft Ir ◽

Doped Titania

Titania pillared clay membranes exhibit unique charge characteristics which are dependent on the solution pH. Doping of such membranes with precious metal like Pt induces a positive charge on the surface of the membranes, thus increasing its resistance against fouling. X-ray Diffraction (XRD) and Fourier Transform Infra-Red Spectroscopy (FT-IR) confirm the complete intercalation of anatase titania in the interlayer spaces of Montmorillonite in the present work. These membranes efficiently removed 83% of the dye from the real textile effluent in a one filtration cycle.

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Influence of synthesis methods on zirconium doped titania photocatalysts

Open Chemistry ◽

10.2478/s11532-009-0112-1 ◽

2010 ◽

Vol 8 (1) ◽

pp. 182-187 ◽

Cited By ~ 9

Author(s):

Narayanan Binitha ◽

Zahira Yaakob ◽

Ramakrishnan Resmi

Keyword(s):

Sol Gel ◽

Chemical Characterization ◽

Synthesis Methods ◽

Electron Microscopic ◽

Preparation Methods ◽

Transmission Electron ◽

Anatase Titania ◽

Volume Measurements ◽

Titania Sol ◽

Doped Titania

AbstractSynthesis of various zirconium doped titania based photocatalysts were carried out by adapting different synthetic strategies. Doping is done on commercially available anatase titania, sol-gel titania and template mediated sol gel titania. A comparative study of the various prepared photocataysts was done using physico-chemical characterization techniques such as X-ray diffraction (XRD), surface area- pore volume measurements, UV-VIS Diffuse reflectance spectra (DRS), elemental analysis (XRF) and transmission electron microscopic (TEM) studies. The effect of zirconium and preparation methods on the photocatalytic degradation of methylorange is studied extensively. Both the surface properties and photo activity of zirconium doped titania were found to have a great dependence on the preparation methods. Among the different photocatalytic systems, the catalyst prepared by doping in the presence of urea template was found to produce a maximum photodegradation of 97.5%.

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Modification of TiO2 nanoparticles through lanthanum doping and peg templating

Processing and Application of Ceramics ◽

10.2298/pac1404195m ◽

2014 ◽

Vol 8 (4) ◽

pp. 195-202 ◽

Cited By ~ 6

Author(s):

Marija Milanovic ◽

Ljubica Nikolic

Keyword(s):

Anatase Phase ◽

Sol Gel ◽

Nitrogen Adsorption ◽

Sem Analysis ◽

X Ray Diffraction ◽

Average Pore ◽

Lanthanum Doping ◽

X Ray ◽

Doped Titania ◽

Adsorption Desorption

Pure and lanthanum doped titania nanopowders were synthesized through a room temperature sol-gel method using a template of polyethylene glycol (PEG). The progress of the synthesis in terms of phase formation and size of nanoparticles was monitored by X-ray diffraction, FTIR spectroscopy and SEM analysis. After calcination at 450?C in air, the results have shown the presence of small particles crystallized predominantly in the form of anatase phase, with significant agglomeration. Nitrogen adsorption-desorption measurements confirmed that all prepared powders are mesoporous with an average pore diameter in range 3.1-3.8 nm. The addition of lanthanum ions leads to the nanopowders with the highest specific surface (BET) area (203m2/g). The obtained powders were compared to TiO2 prepared without a template.

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