Preparation of TiO2 nanoparticles surface-modified by both carboxylic acid and amine: Dispersibility and stabilization in organic solvents

Nakayama, Norio; Hayashi, Tadao

doi:10.1016/j.colsurfa.2007.11.036

Cited by 145 publications

(114 citation statements)

References 18 publications

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“…The autoclave was heated at a rate of 2.67 • C/min just to 30 • C below the set-point temperature, then at a rate of 0.75 • C/min up to 220 • C. TiO 2 surface was functionalized following a modified literature procedure [25]. In anhydrous conditions, 20 mL of the organic reagent (propionic acid, PA; exylamine, EA; 2-methoxyethylamine, MA) was added to 3.30 g of TiO 2 suspended, after ultrasound treatment, in 40 mL of anhydrous methanol.…”

Section: Functionalization Of Tio 2 Nanoparticlesmentioning

confidence: 99%

“…PEG also acts as a carrier of TiO 2 particles into the macropores of silica matrix. In order to disperse TiO 2 nanocrystals in the PEG phase, the oxide particles were functionalized with carboxylic acid or amine derivatives [25], which make the TiO 2 surface less hydrophilic, improving the interactions with the polymeric chains. Subsequent annealing at 500 • C removes both PEG and functionalizing organic molecules and generates the interconnected macroporous silica network.…”

Section: Introductionmentioning

confidence: 99%

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TiO2 nanocrystals grafted on macroporous silica: A novel hybrid organic–inorganic sol–gel approach for the synthesis of highly photoactive composite material

Crippa

Callone

D’Arienzo

et al. 2011

Applied Catalysis B: Environmental

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a b s t r a c tTiO 2 -SiO 2 composite materials with photocatalytic properties similar to those of slurry powdered TiO 2 is obtained by a novel sol-gel synthetic strategy involving the hydrolysis/condensation of TMOS assisted by PEG as templating agent and the grafting of preformed titania nanocrystals onto the macropore walls of the silica matrix. In order to anchor TiO 2 particles to the surface of SiO 2 , avoiding their embedding into silica matrix, functionalization with carboxylic acid or amine derivatives was carried out. The functionalization induces the confinement of titania nanocrystals in PEG, during the silica formation, and allows their dispersion on the silica surface. TiO 2 -SiO 2 materials exhibit high thermal and chemical stability and a photocatalytic activity in the phenol mineralization comparable to that of powder TiO 2 in slurry (half degradation time ∼120 min). These results suggest that the immobilization procedure here reported provides high accessibility of the catalyst active sites preserving the functional properties of the photoactive catalyst.

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Section: Functionalization Of Tio 2 Nanoparticlesmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

TiO2 nanocrystals grafted on macroporous silica: A novel hybrid organic–inorganic sol–gel approach for the synthesis of highly photoactive composite material

Crippa

Callone

D’Arienzo

et al. 2011

Applied Catalysis B: Environmental

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“…After the appropriate surface modification, nanoparticles become hydrophobic, which can decrease their surface tension and lead to better miscibility and compatibility of nanoparticles with the polymer matrix [18]. Organic groups that can be used to attach ligands to the titanium dioxide surface are amine [19], ammonium [20] and different benzene derivatives, mostly catechol and salicylic acid [21][22][23]. Aromatic ligands with two or three adjacent phenolic OH groups (catechol, pyrogallol and gallic acid) can be adsorbed on the surface of TiO 2 by forming chelating or bridging complexes with titanium ions on the surface [24][25].…”

Section: Introductionmentioning

confidence: 99%

Synthesis and characterization of the surface modified titanium dioxide/epoxy nanocomposites

Radoman¹,

Terzic²,

Spasojević³

et al. 2015

Savr tehnol

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TiO 2 nanoparticles, obtained by acid catalyzed hydrolysis of titanium isopropoxide, were surface modified by three gallic acid esters with different hydrophobic part length: octyl, decyl and lauryl gallate, and then used to prepare TiO 2 /epoxy nanocomposites. The characterization of the surface modified TiO 2 nanoparticles was performed by FTIR and UV-Vis spectroscopy. The influence of different gallic acid esters and content of modified TiO 2 nanoparticles on the glass transition temperature (Tg), rheological, barrier and mechanical properties of the nanocomposites was investigated by DSC, DMA, water vapor permeability test and König pendulum. The presence of the surface modified TiO 2 nanoparticles in epoxy resin caused the increase of Tg and decrease of the water vapor permeability. However, the length of the nonpolar gallate part showed no effect on Tg of the synthesized nanocomposites, while the increase of the nanofiller content resulted in the increase of Tg. With increasing the hydrophobic part chain length of gallate ligand, the water vapor transmission rate decreased, while the hardness of the nanocomposites did not change.

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“…They examined an adsorption of amine molecules to investigate the surface adsorption sites. Nakayama and Hyashi prepared stable sols of TiO 2 with surface modification of carboxylic acid and amine [15]. Some reports have also described methods for preparation of TiO 2 nanoparticles and stable sols using peroxotitanic acid as a precursor [16].…”

Section: Introductionmentioning

confidence: 99%

Characterization of Titanium Oxide Nanoparticles Obtained by Hydrolysis Reaction of Ethylene Glycol Solution of Alkoxide

Uekawa

Endo

Ishii

et al. 2012

Journal of Nanotechnology

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Transparent and stable sols of titanium oxide nanoparticles were obtained by heating a mixture of ethylene glycol solution of titanium tetraisopropoxide (TIP) and a NH 3 aqueous solution at 368 K for 24 h. The concentration of NH 3 aqueous solution affected the structure of the obtained titanium oxide nanoparticles. For NH 3 aqueous solution concentrations higher than 0.2 mol/L, a mixture of anatase TiO 2 nanoparticles and layered titanic acid nanoparticles was obtained. The obtained sol was very stable without formation of aggregated precipitates and gels. Coordination of ethylene glycol to Ti 4+ ions inhibited the rapid hydrolysis reaction and aggregation of the obtained nanoparticles. The obtained titanium oxide nanoparticles had a large specific surface area: larger than 350 m 2 /g. The obtained titanium oxide nanoparticles showed an enhanced adsorption towards the cationic dye molecules. The selective adsorption corresponded to presence of layered titanic acid on the obtained anatase TiO 2 nanoparticles.

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Preparation of TiO2 nanoparticles surface-modified by both carboxylic acid and amine: Dispersibility and stabilization in organic solvents

Cited by 145 publications

References 18 publications

TiO2 nanocrystals grafted on macroporous silica: A novel hybrid organic–inorganic sol–gel approach for the synthesis of highly photoactive composite material

TiO2 nanocrystals grafted on macroporous silica: A novel hybrid organic–inorganic sol–gel approach for the synthesis of highly photoactive composite material

Synthesis and characterization of the surface modified titanium dioxide/epoxy nanocomposites

Characterization of Titanium Oxide Nanoparticles Obtained by Hydrolysis Reaction of Ethylene Glycol Solution of Alkoxide

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