The self diffusion of oxygen in Fe3O4 has been studied at 1150 degrees C by means of an oxygen isotopic exchange method. T The experimental value of the oxygen diffusion coefficient D-0* decreases with the oxygen partial pressure in a lower range up to about 10(-7) atm with a slope equal to 1/2, while at higher P-O2 it increases with a slope of about 1/6. These results are attributed to a change in the nature of the defects in the oxygen sublattice. At low P-O2, where the majority defects are iron interstitials, the prevailing oxygen defects are free oxygen vacancies. At high P-O2, where the majority defects are cation vacancies, the observed slope supports the presence of clusters of metal vacancies with oxygen vacancies formed as a result of the Coulombic attractions. A general discussion of the properties of minority defects in oxides is also presented. (C) 1996 Elsevier Science Ltd.
部门归属
acad sinica,inst corros & protect met,state key lab corros & protect,shenyang 110015,peoples r china.;millot, f (reprint author), univ paris 11,composes nonstoechiometr lab,batiment 415,f-91405 orsay,france
F. Millot,Y. Niu. Diffusion of O-18 in Fe3O4: An experimental approach to study the behavior of minority defects in oxides[J]. Journal of Physics and Chemistry of Solids,1997,58(1):63-72.
APA
F. Millot,&Y. Niu.(1997).Diffusion of O-18 in Fe3O4: An experimental approach to study the behavior of minority defects in oxides.Journal of Physics and Chemistry of Solids,58(1),63-72.
MLA
F. Millot,et al."Diffusion of O-18 in Fe3O4: An experimental approach to study the behavior of minority defects in oxides".Journal of Physics and Chemistry of Solids 58.1(1997):63-72.
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