TY  - JOUR
AU  - Stanciu, Irina
AU  - Predoana, Luminita
AU  - Cusu, Jeanina Pandele
AU  - Preda, Silviu
AU  - Anastasescu, Mihai
AU  - Vojisavljević, Katarina
AU  - Malic, Barbara
AU  - Zaharescu, Maria
PY  - 2017
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/1040
AB  - In order to establish the influence of the preparation method on thermal behaviour of gels obtained by the sol-gel and microwave-assisted sol-gel methods, a comparative thermal analysis study was conducted by the thermogravimetric and differential thermal analysis (TG/DTG/DTA) and evolved gas analysis (EGA) on TiO2 and V2O5-doped TiO2 gels, where TiO2:V2O5 molar ratio was set to 99.95:0.05 and 98.0:2.0. In contrast to TiO2 gels, for which the thermal behaviour was not significantly influenced by the preparation method, the microwave-irradiated binary samples showed a more complex and prolonged decomposition compared to their non-irradiated counterparts. This observation was correlated with influence of microwaves in enhancing the reaction rate between the Ti and V reagents leading to formation of more complex compositions of gels. Based on TG/DTG/DTA results, the temperatures of 300 and 450 A degrees C were chosen for the processing of powders in air. All samples thermally treated at 300 and 450 A degrees C crystallized in a single anatase phase except the TiO2:V2O5 with a molar ratio 99.95:0.05, obtained by microwave-assisted sol-gel method that contains also small amount of rutile phase. At 550 A degrees C all samples contain mixture of anatase and rutile phases.
PB  - Springer, Dordrecht
T2  - Journal of Thermal Analysis and Calorimetry
T1  - Thermal behaviour of the TiO2-based gels obtained by microwave-assisted sol-gel method
EP  - 651
IS  - 2
SP  - 639
VL  - 130
DO  - 10.1007/s10973-017-6478-y
ER  - 

@article{
author = "Stanciu, Irina and Predoana, Luminita and Cusu, Jeanina Pandele and Preda, Silviu and Anastasescu, Mihai and Vojisavljević, Katarina and Malic, Barbara and Zaharescu, Maria",
year = "2017",
abstract = "In order to establish the influence of the preparation method on thermal behaviour of gels obtained by the sol-gel and microwave-assisted sol-gel methods, a comparative thermal analysis study was conducted by the thermogravimetric and differential thermal analysis (TG/DTG/DTA) and evolved gas analysis (EGA) on TiO2 and V2O5-doped TiO2 gels, where TiO2:V2O5 molar ratio was set to 99.95:0.05 and 98.0:2.0. In contrast to TiO2 gels, for which the thermal behaviour was not significantly influenced by the preparation method, the microwave-irradiated binary samples showed a more complex and prolonged decomposition compared to their non-irradiated counterparts. This observation was correlated with influence of microwaves in enhancing the reaction rate between the Ti and V reagents leading to formation of more complex compositions of gels. Based on TG/DTG/DTA results, the temperatures of 300 and 450 A degrees C were chosen for the processing of powders in air. All samples thermally treated at 300 and 450 A degrees C crystallized in a single anatase phase except the TiO2:V2O5 with a molar ratio 99.95:0.05, obtained by microwave-assisted sol-gel method that contains also small amount of rutile phase. At 550 A degrees C all samples contain mixture of anatase and rutile phases.",
publisher = "Springer, Dordrecht",
journal = "Journal of Thermal Analysis and Calorimetry",
title = "Thermal behaviour of the TiO2-based gels obtained by microwave-assisted sol-gel method",
pages = "651-639",
number = "2",
volume = "130",
doi = "10.1007/s10973-017-6478-y"
}

Stanciu, I., Predoana, L., Cusu, J. P., Preda, S., Anastasescu, M., Vojisavljević, K., Malic, B.,& Zaharescu, M.. (2017). Thermal behaviour of the TiO2-based gels obtained by microwave-assisted sol-gel method. in Journal of Thermal Analysis and Calorimetry
Springer, Dordrecht., 130(2), 639-651.
https://doi.org/10.1007/s10973-017-6478-y

Stanciu I, Predoana L, Cusu JP, Preda S, Anastasescu M, Vojisavljević K, Malic B, Zaharescu M. Thermal behaviour of the TiO2-based gels obtained by microwave-assisted sol-gel method. in Journal of Thermal Analysis and Calorimetry. 2017;130(2):639-651.
doi:10.1007/s10973-017-6478-y .

Stanciu, Irina, Predoana, Luminita, Cusu, Jeanina Pandele, Preda, Silviu, Anastasescu, Mihai, Vojisavljević, Katarina, Malic, Barbara, Zaharescu, Maria, "Thermal behaviour of the TiO2-based gels obtained by microwave-assisted sol-gel method" in Journal of Thermal Analysis and Calorimetry, 130, no. 2 (2017):639-651,
https://doi.org/10.1007/s10973-017-6478-y . .

TY  - JOUR
AU  - Zaharescu, M.
AU  - Mihaiu, S.
AU  - Toader, A.
AU  - Atkinson, I.
AU  - Calderon-Moreno, J.
AU  - Anastasescu, M.
AU  - Nicolescu, M.
AU  - Duta, M.
AU  - Gartner, M.
AU  - Vojisavljević, Katarina
AU  - Malic, Barbara
AU  - Ivanov, V. A.
AU  - Zaretskaya, E. P.
PY  - 2014
UR  - http://rimsi.imsi.bg.ac.rs/handle/123456789/816
AB  - The transparent conductive oxide films with controlled type of conduction are of great importance and their preparation is intensively studied. In our work, the preparation of such films based on doped ZnO was realized in order to achieve controlled type of conduction and high concentration of the charge carriers. Sol-gel method was used for films preparation and several dopants were tested (Sn, Li, Ni). Multilayer deposition was performed on several substrates: SiO2/Si wafers, silica-soda-lime and/or silica glasses. The structural and morphological characterization of the obtained films were done by scanning electron microscopy, X-ray diffraction, X-ray fluorescence, X-ray photoelectron spectroscopy and atomic force microscopy respectively, while spectroscopic ellipsometry and transmittance measurements were done for determination of optical properties. The selected samples with the best structural, morphological and optical properties were subjected to electrical measurement (Hall and Seebeck effect). In all studied cases, samples with good adherence and homogeneous morphology as well as monophasic wurtzite type structure were obtained. The optical constants (refractive index and extinction coefficient) were calculated from spectroscopic ellipsometry data using Cauchy model. Films with n- or p-type conduction were obtained depending on the composition, number of deposition and thermal treatment temperature.
PB  - Elsevier Science Sa, Lausanne
T2  - Thin Solid Films
T1  - ZnO based transparent conductive oxide films with controlled type of conduction
EP  - 734
SP  - 727
VL  - 571
DO  - 10.1016/j.tsf.2014.02.090
ER  - 

@article{
author = "Zaharescu, M. and Mihaiu, S. and Toader, A. and Atkinson, I. and Calderon-Moreno, J. and Anastasescu, M. and Nicolescu, M. and Duta, M. and Gartner, M. and Vojisavljević, Katarina and Malic, Barbara and Ivanov, V. A. and Zaretskaya, E. P.",
year = "2014",
abstract = "The transparent conductive oxide films with controlled type of conduction are of great importance and their preparation is intensively studied. In our work, the preparation of such films based on doped ZnO was realized in order to achieve controlled type of conduction and high concentration of the charge carriers. Sol-gel method was used for films preparation and several dopants were tested (Sn, Li, Ni). Multilayer deposition was performed on several substrates: SiO2/Si wafers, silica-soda-lime and/or silica glasses. The structural and morphological characterization of the obtained films were done by scanning electron microscopy, X-ray diffraction, X-ray fluorescence, X-ray photoelectron spectroscopy and atomic force microscopy respectively, while spectroscopic ellipsometry and transmittance measurements were done for determination of optical properties. The selected samples with the best structural, morphological and optical properties were subjected to electrical measurement (Hall and Seebeck effect). In all studied cases, samples with good adherence and homogeneous morphology as well as monophasic wurtzite type structure were obtained. The optical constants (refractive index and extinction coefficient) were calculated from spectroscopic ellipsometry data using Cauchy model. Films with n- or p-type conduction were obtained depending on the composition, number of deposition and thermal treatment temperature.",
publisher = "Elsevier Science Sa, Lausanne",
journal = "Thin Solid Films",
title = "ZnO based transparent conductive oxide films with controlled type of conduction",
pages = "734-727",
volume = "571",
doi = "10.1016/j.tsf.2014.02.090"
}

Zaharescu, M., Mihaiu, S., Toader, A., Atkinson, I., Calderon-Moreno, J., Anastasescu, M., Nicolescu, M., Duta, M., Gartner, M., Vojisavljević, K., Malic, B., Ivanov, V. A.,& Zaretskaya, E. P.. (2014). ZnO based transparent conductive oxide films with controlled type of conduction. in Thin Solid Films
Elsevier Science Sa, Lausanne., 571, 727-734.
https://doi.org/10.1016/j.tsf.2014.02.090

Zaharescu M, Mihaiu S, Toader A, Atkinson I, Calderon-Moreno J, Anastasescu M, Nicolescu M, Duta M, Gartner M, Vojisavljević K, Malic B, Ivanov VA, Zaretskaya EP. ZnO based transparent conductive oxide films with controlled type of conduction. in Thin Solid Films. 2014;571:727-734.
doi:10.1016/j.tsf.2014.02.090 .

Zaharescu, M., Mihaiu, S., Toader, A., Atkinson, I., Calderon-Moreno, J., Anastasescu, M., Nicolescu, M., Duta, M., Gartner, M., Vojisavljević, Katarina, Malic, Barbara, Ivanov, V. A., Zaretskaya, E. P., "ZnO based transparent conductive oxide films with controlled type of conduction" in Thin Solid Films, 571 (2014):727-734,
https://doi.org/10.1016/j.tsf.2014.02.090 . .