TiO2 powders synthesized by pressurized fluid extraction and supercritical drying: Effect of water and methanol on structural properties and purity

Matějová, Lenka; Matěj, Zdeněk; Fajgаr, Radek; Cajthaml, Tomáš; Šolcová, Olga

doi:10.1016/j.materresbull.2012.06.062

Cited by 22 publications

(9 citation statements)

References 43 publications

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“…23,[28][29][30][31] Triton-X has been used basically in the preparation of titania by pressurized uid extraction and supercritical drying methods. 4,6,7,[32][33][34][35] Several studies have been published in which reverse micelles have been used in the synthesis of nanoporous materials. In this paper, we present the rst systematic study of the synthesis of porous titanium dioxide with the use of electrically neutral amphiphilic molecules of the so-called Triton-X series forming reverse micelles.…”

Section: 21mentioning

confidence: 99%

Tuning the porosity and surface characteristics of nanoporous titania using non-ionic surfactant reverse micelles

Paschalidou

Theocharis

2018

RSC Adv.

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Nanoporous titania was prepared from non-ionic surfactant reverse micelles (e.g. Triton-X) and the effects of the chain length of the surfactants and calcination temperature of the precursor gels on the surface properties of the product (mesoporous titania) were investigated. The studies included sample characterization of the precursor gels from the titania samples characterized by UV-Vis, ATR-FTIR, XRD, TGA/DSC and the titania samples by N 2 -adsorption BET, XRD, FT-IR, UV-Vis diffuse reflectance and SEM measurements after calcination at 400 C, 500 C, 600 C, 700 C and 800 C. According to the experimental results, generally increasing the length of the polar tail of Triton-X results in an increased specific surface area and volume, and an average pore diameter of the solids. Moreover, increasing the length of the polar tail is associated with a smaller crystallite size and higher thermal stability of the materials. Finally, a nucleation mechanism of the titania particles within the aqueous centre of the reversed micelles is proposed.

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Section: 21mentioning

confidence: 99%

Tuning the porosity and surface characteristics of nanoporous titania using non-ionic surfactant reverse micelles

Paschalidou

Theocharis

2018

RSC Adv.

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“…The sol-gel preparation of TiO 2 was described in detail in previous works [25,27]. The prepared titania gel was crushed into small grains (∼2 × 2 × 2 mm 3 ) and processed under pressurized hot water and methanol or ethanol in order to produce nanostructured TiO 2 in the powder form.…”

Section: Preparation and Characterization Of Tio 2 Photocatalystsmentioning

confidence: 99%

“…Along removal of organic part the specific surface area increases. Moreover, this method allows to prepare anatase-brookite composites [25]. It has been reported the TiO 2 photocatalyst composed from 2 different phases is more photocatalytically active than the one composed from only one phase.…”

Section: Introductionmentioning

confidence: 99%

TiO2 Processed by pressurized hot solvents as a novel photocatalyst for photocatalytic reduction of carbon dioxide

Reli

Kobielusz

Matějová

et al. 2017

Applied Surface Science

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“…For more details about the extraction setup, see [31]. The gel sample placed in 24-mL high-temperature stainless steel cell was extracted/processed in a flow regime at 10 MPa and 200°C, using 1.05 L of deionized water and 0.5 L of methanol.…”

Section: Preparation Of Tio 2 Photocatalystsmentioning

confidence: 99%

Preparation, characterization and photocatalytic performance of TiO2 prepared by using pressurized fluids in CO2 reduction and N2O decomposition

Kočí

Matějová

Obalová

et al. 2015

J Sol-Gel Sci Technol

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TiO 2 photocatalyst was prepared unconventionally, using the sol-gel process controlled within the reverse micelles and the processing by pressurized hot fluids as an alternative to standard calcination. Conventional calcined TiO 2 was prepared as well. Textural, microstructural and optical properties of prepared photocatalysts were characterized by using nitrogen physisorption, powder X-ray diffraction and DR UV-Vis spectroscopy. The photocatalytic properties of developed TiO 2 catalysts were investigated in the photocatalytic reduction of CO 2 and photocatalytic decomposition of N 2 O. It was revealed that TiO 2 processed by pressurized hot fluids shows significantly improved textural properties and different crystallinity compared to its calcined analog. Yields of both reaction products (H 2 and CH 4 ) of CO 2 photoreduction were higher for the extracted TiO 2 photocatalyst. The same result was achieved in N 2 O photodecomposition. The maximum N 2 O conversion (83 % after 20 h of illumination) in inert gas was reached also over the TiO 2 extracted photocatalyst, and it can be attributed to simultaneous N 2 O photocatalytic decomposition and N 2 O photolysis. Reaction kinetics of N 2 O-photoinduced decomposition was described well by the pseudo-first-rate law. The surface heterojunction of bicrystalline anatase-brookite phase corresponded to better catalytic activity of TiO 2 processed by pressurized hot fluids in both reactions, in a consequence of reduced electron-hole pair recombination. Graphical Abstract& Kamila Kočí

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TiO2 powders synthesized by pressurized fluid extraction and supercritical drying: Effect of water and methanol on structural properties and purity

Cited by 22 publications

References 43 publications

Tuning the porosity and surface characteristics of nanoporous titania using non-ionic surfactant reverse micelles

Tuning the porosity and surface characteristics of nanoporous titania using non-ionic surfactant reverse micelles

TiO2 Processed by pressurized hot solvents as a novel photocatalyst for photocatalytic reduction of carbon dioxide

Preparation, characterization and photocatalytic performance of TiO2 prepared by using pressurized fluids in CO2 reduction and N2O decomposition

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