By a News Reporter-Staff News Editor at Life Science Weekly -- Current study results on Chalcogens have been published. According to news reporting originating from Milano, Italy, by NewsRx correspondents, research stated, "Methods and models describing oxygen diffusion and desorption in oxides have been developed for slightly defective and well crystallised bulky materials. Does nanostructuring change the mechanism of oxygen mobility? In such a case, models should be properly checked and adapted to take into account new material properties."
Our news editors obtained a quote from the research from the University of Milan, "In order to do so, temperature programmed oxygen desorption and thermogravimetric analysis, either in isothermal or ramp mode, have been used to investigate some nanostructured La1-xAxMnO3±? samples (A=Sr and Ce, 20-60 nm particle size) with perovskite-like structure. The experimental data have been elaborated by means of different models to define a set of kinetic parameters able to describe oxygen release properties and oxygen diffusion through the bulk. Different rate-determining steps have been identified, depending on the temperature range and oxygen depletion of the material. In particular, oxygen diffusion was shown to be rate-limiting at low temperature and at low defect concentration, whereas oxygen recombination at the surface seems to be the rate-controlling step at high temperature. However, the oxygen recombination step is characterised by an activation energy much lower than that for diffusion."
According to the news editors, the research concluded: "In the present paper oxygen transport in nanosized materials is quantified by making use of widely diffused experimental techniques and by critically adapting to nanoparticles suitably chosen models developed for bulk materials."
For more information on this research see: Oxygen transport in nanostructured lanthanum manganites. Physical Chemistry Chemical Physics, 2013;15(39):16779-87. (Royal Society of Chemistry - www.rsc.org/; Physical Chemistry Chemical Physics - pubs.rsc.org/en/journals/journalissues/cp)
The news editors report that additional information may be obtained by contacting I. Rossetti, Dip Chimica, Universita degli Studi di Milano, CNR-ISTM center and INSTM Milano-Universita, Unit v C Golgi 19, I-20133 Milano, Italy. Additional authors for this research include M. Allieta, C. Biffi and M. Scavini (see also Chalcogens).
Keywords for this news article include: Italy, Milano, Europe, Lanthanum, Chalcogens, Lanthanoid Series Elements.
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