Pregled bibliografske jedinice broj: 205362
Dielectric behaviour of chromium iron phosphate glasses
Dielectric behaviour of chromium iron phosphate glasses // Book of Abstracts of the 5th International Discussion Meeting on Relaxations in Complex Systems / Descamps, Marc ; Affouard, Frederic ; Ngai Kia L. (ur.).
Lille: Universite des Sciences et Technologies de Lille, 2005. (poster, međunarodna recenzija, sažetak, znanstveni)
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Naslov
Dielectric behaviour of chromium iron phosphate glasses
Autori
Šantić, Ana ; Moguš-Milanković, Andrea ; Day, Delbert E.
Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni
Izvornik
Book of Abstracts of the 5th International Discussion Meeting on Relaxations in Complex Systems
/ Descamps, Marc ; Affouard, Frederic ; Ngai Kia L. - Lille : Universite des Sciences et Technologies de Lille, 2005
Skup
5th International Discussion Meeting on Relaxations in Complex Systems
Mjesto i datum
Lille, Francuska, 07.07.2005. - 13.07.2005
Vrsta sudjelovanja
Poster
Vrsta recenzije
Međunarodna recenzija
Ključne riječi
chromium iron phosphate glasses; deilectric properties
Sažetak
The relationship between structure and electrical/dielectric properties for glass system xCr2O3-(100-x)[40Fe2O3-60P2O5], (0 x 15, in mol%) has been investigated by Raman and impedance spectroscopy. Experimental impedance spectra were interpreted by means of equivalent circuit modelling, using complex non-linear least square (CNLLSQ) procedure. The Raman spectra of glasses with up to 10 mol% of Cr2O3 show predominantly pyrophosphate structure. With increasing Cr2O3 content  10 mol% high tendency for crystallization was observed which was confirmed with XRD. The electrical properties of chromium iron phosphate glasses show strong dependence on concentration of Fe(II) ions. Although the Fe2O3 content decreases slightly from 40 to 34 mol%, the electrical conductivity increases from 4.9x10-9 to 7.7x10-8 ( m)-1 at 303 K due to increase in Fe(II) fraction from 15 to 51% in these glasses. An increase in Fe(II) concentration with increasing Cr2O3 content indicates a possible redox process between iron and chromium ions during glass melting. The evolution of the complex dielectric permittivity as a function of frequency and temperature was investigated. The thermal activated relaxation mechanism dominates the observed relaxation behavior. The relationship between relaxation parameters and electrical conductivity indicates that the electronic conductivity is controlled by polaron hopping between iron ions.
Izvorni jezik
Engleski
Znanstvena područja
Kemija
