TY  - JOUR
AU  - Stošić, Dušan
AU  - Bennici, Simona
AU  - Pavlović, Vladimir
AU  - Rakić, Vesna
AU  - Auroux, Aline
PY  - 2014
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/3409
AB  - Mesoporous Nb2O5 MeO2 (Me = Ti, Zr, Ce) mixed oxides were successfully prepared using evaporation-induced self-assembly (EISA) method. The structural and textural properties of these materials have been fully characterized using appropriate techniques (low-temperature adsorption-desorption of nitrogen, thermogravimetric analysis, X-ray diffraction analysis (XRD) transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Raman spectroscopy). Acid-base properties were estimated by adsorption microcalorimetry of NH3 and SO2 molecules in order to determine the population, strength and strength distribution of acidic or basic sites. Formation of mesoporous structure was confirmed by the results of XRD, TEM and BET techniques. Results of adsorption microcalorimetry technique showed that the type of transition metal oxide added to niobia has a decisive role for acidic-basic character of investigated mixed oxides. Among the investigated mixed oxide formulations only Nb2O5-CeO2 was amphoteric, while the other samples showed prominent acidic character. All the investigated materials are catalytically active in fructose dehydration; conversion of fructose and selectivity to 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) are proved to be dependant on the number of acidic sites on the surface of catalysts. Furthermore, presence of the basic sites on the surface of the catalyst decreases the activity in the fructose dehydration reaction, as in the case of Nb2O5-CeO2 sample.
PB  - Elsevier Science Sa, Lausanne
T2  - Materials Chemistry and Physics
T1  - Tuning the acidity of niobia: Characterization and catalytic activity of Nb2O5-MeO2 (Me = Ti, Zr, Ce) mesoporous mixed oxides
EP  - 345
IS  - 3
SP  - 337
VL  - 146
DO  - 10.1016/j.matchemphys.2014.03.033
ER  - 

@article{
author = "Stošić, Dušan and Bennici, Simona and Pavlović, Vladimir and Rakić, Vesna and Auroux, Aline",
year = "2014",
abstract = "Mesoporous Nb2O5 MeO2 (Me = Ti, Zr, Ce) mixed oxides were successfully prepared using evaporation-induced self-assembly (EISA) method. The structural and textural properties of these materials have been fully characterized using appropriate techniques (low-temperature adsorption-desorption of nitrogen, thermogravimetric analysis, X-ray diffraction analysis (XRD) transmission electron microscopy (TEM), scanning electron microscopy (SEM) and Raman spectroscopy). Acid-base properties were estimated by adsorption microcalorimetry of NH3 and SO2 molecules in order to determine the population, strength and strength distribution of acidic or basic sites. Formation of mesoporous structure was confirmed by the results of XRD, TEM and BET techniques. Results of adsorption microcalorimetry technique showed that the type of transition metal oxide added to niobia has a decisive role for acidic-basic character of investigated mixed oxides. Among the investigated mixed oxide formulations only Nb2O5-CeO2 was amphoteric, while the other samples showed prominent acidic character. All the investigated materials are catalytically active in fructose dehydration; conversion of fructose and selectivity to 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) are proved to be dependant on the number of acidic sites on the surface of catalysts. Furthermore, presence of the basic sites on the surface of the catalyst decreases the activity in the fructose dehydration reaction, as in the case of Nb2O5-CeO2 sample.",
publisher = "Elsevier Science Sa, Lausanne",
journal = "Materials Chemistry and Physics",
title = "Tuning the acidity of niobia: Characterization and catalytic activity of Nb2O5-MeO2 (Me = Ti, Zr, Ce) mesoporous mixed oxides",
pages = "345-337",
number = "3",
volume = "146",
doi = "10.1016/j.matchemphys.2014.03.033"
}

Stošić, D., Bennici, S., Pavlović, V., Rakić, V.,& Auroux, A.. (2014). Tuning the acidity of niobia: Characterization and catalytic activity of Nb2O5-MeO2 (Me = Ti, Zr, Ce) mesoporous mixed oxides. in Materials Chemistry and Physics
Elsevier Science Sa, Lausanne., 146(3), 337-345.
https://doi.org/10.1016/j.matchemphys.2014.03.033

Stošić D, Bennici S, Pavlović V, Rakić V, Auroux A. Tuning the acidity of niobia: Characterization and catalytic activity of Nb2O5-MeO2 (Me = Ti, Zr, Ce) mesoporous mixed oxides. in Materials Chemistry and Physics. 2014;146(3):337-345.
doi:10.1016/j.matchemphys.2014.03.033 .

Stošić, Dušan, Bennici, Simona, Pavlović, Vladimir, Rakić, Vesna, Auroux, Aline, "Tuning the acidity of niobia: Characterization and catalytic activity of Nb2O5-MeO2 (Me = Ti, Zr, Ce) mesoporous mixed oxides" in Materials Chemistry and Physics, 146, no. 3 (2014):337-345,
https://doi.org/10.1016/j.matchemphys.2014.03.033 . .

TY  - CONF
AU  - Stošić, Dušan
AU  - Bennici, Simona
AU  - Rakić, Vesna
AU  - Auroux, Aline
PY  - 2012
UR  - http://aspace.agrif.bg.ac.rs/handle/123456789/2987
AB  - In this work, ceria-niobia mixed oxides have been prepared by coprecipitation. The structural, textural, and surface properties of these materials have been fully characterized using appropriate techniques (low-temperature adsorption-desorption of nitrogen, thermogravimetric analysis, X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and temperature-programmed reduction/oxidation (TPR/O)). The acid-base properties were estimated by the adsorption of appropriate probe molecules - NH3 or SO2 were used to estimate the population, strength and strength distribution of acid or basic sites, by means of adsorption microcalorimetry. The nature of acidic sites was determined through the adsorption/desorption of pyridine, studied by infrared spectroscopy. New phases between the oxides were not formed, while there is evidence of interaction between them, as revealed by XRD and Raman spectroscopy. All investigated mixed oxide samples are amphoteric and possess red-ox centers on their surface. Both red-ox and acid-base properties are dependent on the ratio of ceria to niobia in the samples. Both Lewis and Brnsted acid sites are present on the surface of the mixed oxides. In order to check catalytic abilities of these materials, reaction of fructose dehydration has been performed. All the investigated materials are catalytically active in fructose dehydration; conversion of fructose and selectivity to 5-hydroxymethylfurfural (5-HMF) improved with increasing content of niobia in the samples.
PB  - Elsevier Science Bv, Amsterdam
C3  - Catalysis Today
T1  - CeO2-Nb2O5 mixed oxide catalysts: Preparation, characterization and catalytic activity in fructose dehydration reaction
EP  - 168
IS  - 1
SP  - 160
VL  - 192
DO  - 10.1016/j.cattod.2011.10.040
ER  - 

@conference{
author = "Stošić, Dušan and Bennici, Simona and Rakić, Vesna and Auroux, Aline",
year = "2012",
abstract = "In this work, ceria-niobia mixed oxides have been prepared by coprecipitation. The structural, textural, and surface properties of these materials have been fully characterized using appropriate techniques (low-temperature adsorption-desorption of nitrogen, thermogravimetric analysis, X-ray diffraction analysis (XRD), X-ray photoelectron spectroscopy (XPS), Raman spectroscopy and temperature-programmed reduction/oxidation (TPR/O)). The acid-base properties were estimated by the adsorption of appropriate probe molecules - NH3 or SO2 were used to estimate the population, strength and strength distribution of acid or basic sites, by means of adsorption microcalorimetry. The nature of acidic sites was determined through the adsorption/desorption of pyridine, studied by infrared spectroscopy. New phases between the oxides were not formed, while there is evidence of interaction between them, as revealed by XRD and Raman spectroscopy. All investigated mixed oxide samples are amphoteric and possess red-ox centers on their surface. Both red-ox and acid-base properties are dependent on the ratio of ceria to niobia in the samples. Both Lewis and Brnsted acid sites are present on the surface of the mixed oxides. In order to check catalytic abilities of these materials, reaction of fructose dehydration has been performed. All the investigated materials are catalytically active in fructose dehydration; conversion of fructose and selectivity to 5-hydroxymethylfurfural (5-HMF) improved with increasing content of niobia in the samples.",
publisher = "Elsevier Science Bv, Amsterdam",
journal = "Catalysis Today",
title = "CeO2-Nb2O5 mixed oxide catalysts: Preparation, characterization and catalytic activity in fructose dehydration reaction",
pages = "168-160",
number = "1",
volume = "192",
doi = "10.1016/j.cattod.2011.10.040"
}

Stošić, D., Bennici, S., Rakić, V.,& Auroux, A.. (2012). CeO2-Nb2O5 mixed oxide catalysts: Preparation, characterization and catalytic activity in fructose dehydration reaction. in Catalysis Today
Elsevier Science Bv, Amsterdam., 192(1), 160-168.
https://doi.org/10.1016/j.cattod.2011.10.040

Stošić D, Bennici S, Rakić V, Auroux A. CeO2-Nb2O5 mixed oxide catalysts: Preparation, characterization and catalytic activity in fructose dehydration reaction. in Catalysis Today. 2012;192(1):160-168.
doi:10.1016/j.cattod.2011.10.040 .

Stošić, Dušan, Bennici, Simona, Rakić, Vesna, Auroux, Aline, "CeO2-Nb2O5 mixed oxide catalysts: Preparation, characterization and catalytic activity in fructose dehydration reaction" in Catalysis Today, 192, no. 1 (2012):160-168,
https://doi.org/10.1016/j.cattod.2011.10.040 . .