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Quantitative determination of the kinetics of the reaction of NiO and Al 2 O 3 to NiAl 2 O 4 by Rutherford backscattering

1983; Wiley; Volume: 5; Issue: 3 Linguagem: Inglês

10.1002/sia.740050308

1096-9918

Goedele Roos, J.M. Fluit, Robert P. Velthuizen, J.H.W. de Wit, J.W. Geus,

Copper-based nanomaterials and applications

Abstract A quantitative evaluation of RBS data resulted in data for the parabolic reaction rate constants for the reaction between Al 2 O 3 and NiO at temperatures from 960°C up to 1105°C. The activation energy and the preexponential factor were in good agreement with literature data. The experimental data of this work also permitted a detailed description of reaction mechanisms on a microscopic level. The reaction between Al 2 O 3 and NiO starts with penetration of Al 3+ ions along the grain boundaries of NiO, followed by counter‐diffusion of Ni 2+ ions. A thin spinel layer (NiAl 2 O 4 ) is formed at the Al 2 O 3 /NiO interface, after a relatively short nucleation period. The reaction then proceeds, both by lateral and perpendicular diffusion. In an appendix, the detailed evaluation procedure of the spectra was described.