Determination of niobium diffusion in titania and zirconia using secondary ion mass spectrometry

Abstract

This paper provides an outline for the use of secondary ion mass spectrometry (SIMS) in the determination of diffusion data in metal oxides. The focus is on the determination of Nb bulk and grain boundary diffusion coefficients in TiO₂ and zirconia. Specifically, the diffusion of Nb in TiO₂ and yttria doped (10 mol.-%) ZrO₂ (10YSZ) has been assessed. The following bulk diffusion coefficients D _93Nb were obtained

D _93Nb =(1·03±0·051) × 10⁻¹⁸ m² s⁻¹ 10YSZ(1273K)

D _93Nb =(1·91±0·096) × 10⁻¹⁶ m² s⁻¹ TiO₂(1273K)

The grain boundary diffusion parameter for Nb grain boundary diffusion in 10YSZ was also determined

D _93Nb δα =(7·48 ± 0·37) × 10⁻²⁵ m² s⁻¹ 10YSZ(1273K)

The Nb grain boundary diffusion coefficient D′_93Nb was determined to be

D′_93Nb =(3·99 ± 0·20) × 10⁻¹⁶ m² s⁻¹ 10YSZ(1273K)

Keywords:

• BULK DIFFUSION
• GRAIN BOUNDARY DIFFUSION
• SECONDARY ION MASS SPECTROMETRY
• TITANIA
• ZIRCONIA
• NIOBIUM