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Journal of Thermal Analysis and Calorimetry
Authors: M. Ştefănescu, O. Ştefănescu, M. Stoia, and C. Lazau

Abstract  

In this paper we present a study on the synthesis of Fe(III) oxide, by thermal decomposition of some complex combinations of Fe(III) with carboxylate type ligands, obtained in the redox reaction between some polyols (ethylene glycol (EG), 1,2-propane diol (1,2PG), 1,3-propane diol (1,3PG) and glycerol (GL)) and NO3 ions (from ferric nitrate). Fe2O3 was obtained by thermal decomposition of the synthesized metal-organic precursors at low temperatures. γ-Fe2O3 was obtained as nanoparticles at 300C, while at higher temperatures α-Fe2O3 starts to crystallize and becomes single phase at ~500C. The formation of the metal-organic precursors and their thermal decomposition were studied by thermal analysis and FTIR spectroscopy. The evolution of Fe2O3 crystalline phases with the thermal treatment of iron complexes was followed by RX diffractometry. The size of γ-Fe2O3 nanoparticles was estimated by transmission electron microscopy (TEM).

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Abstract  

Thermal decomposition of metal-organic precursors for the mixed oxide BaBiO3 was studied using TG and EGA. Precursors produced by polyesterification of bifunctional acids with ethylene glycol (Pechini process) decomposed about 100°C higher than those without the diol. BaCO3 was identified by IR and XRD as a reaction intermediate. EGA proved that the amount of BaCO3 was below 10% of the total barium, and that the barium exists mainly as a nitro-compound up to 650°C. Phase-pure BaBiO3 with a moderately high surface area (1.4 m2/g) could be synthesised from a citrate precursor by the Pechini process at around 850°C.

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Non-isothermal model-free predictions

Application to the formation of yttria from yttrium trifluoroacetate

Journal of Thermal Analysis and Calorimetry
Authors: Hichem Eloussifi, Jordi Farjas, Pere Roura, and Mohamed Dammak

Abstract

Suitable thermal treatment of metal organic precursors is a key process to obtain oxide films. To this purpose, non-isothermal model-free predictions are specially suited. In this article we will explore the ability of these methods to provide an accurate prediction of the evolution of the decomposition of yttrium trifluoroacetate, a precursor used in the synthesis of YBaCuO superconducting thin-films. A good agreement has been obtained between the predicted and the measured reaction courses.

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Abstract  

Copper chromite catalysts were prepared by using a new metal organic precursor, M(OR)n, which was dissolved in organic solvent, hydrolysed and condensed to form inorganic polymers containing M-O-M linkages. In the cases of Ba and Mn promotion, the corresponding metal oxide was admixed to the copper-chromium solution prior to gelification. After drying in helium atmosphere, the precursor was subjected to thermal treatment at different temperatures (373-873 K) and in different atmospheres (air, nitrogen or hydrogen). Both the catalysts and the industrial Engelhard catalyst were characterized by various techniques (TG-DTA, HTXRD, IR, BET, metallic copper surface area and porosimetry measurements) and evaluated for ester hydrogenation.

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metal nitrates and propanediol . Acta Chim Slov 56 : 379 – 385 . 23. Ştefănescu , M , Ştefănescu , O , Stoia , M , Lazau , C 2007 Thermal decomposition of some metal-organic

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between metal nitrates and 1,3-propanediol, with formation of the complex combinations inside the hybrid gels. The gels were thermally treated at 300 °C when the oxidative decomposition of the metal–organic precursors took place with formation of the

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Journal of Thermal Analysis and Calorimetry
Authors: Kseniya V. Zherikova, Ludmila N. Zelenina, Natalia B. Morozova, and Tamara P. Chusova

, Gelfond , NV , Mischenko , AV , Norman , JA 2007 Approach to control deposition of ultra thin films from metal organic precursors: Ru deposition . Surf Coat Technol. 201 : 9003 – 9008 10.1016/j.surfcoat.2007

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cocatalyst [ 18 ]. Owing to the utility of niobium oxides and mixed oxides as effective catalysts in many processes, the synthesis of metal–organic precursors affording these oxides has assumed remarkable importance. In this context, phenomenal interest in

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, Ştefănescu , O , Stoia , M , Lazau , C 2007 Thermal decomposition of some metal-organic precursors Fe 2 O 3 nanoparticles . J Therm Anal Calorim 881 : 27 – 32 . 7. Stefanescu , M

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complex shapes and to produce thin films without the need for machining or melting and this method is waste-free and excludes the stage of washing [ 1 – 9 ]. The most widely used metal–organic precursors for the preparation of materials by sol

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