The observation of water penetration into Na-beta-alumina by 1H( 15N, α γ) 12C reaction

Abstract

Water penetration into Na-beta-alumina has been followed by 1H ( 15N, α γ) 12C reaction. The uptake of water by beta-alumina occurs in two steps and is reversible upon heating. The average intercalated water estimated from the hydrogen concentration is about 1 H 2O per unit cell for the monocrystal. The diffusion coefficient deduced from the hydrogen profile in beta-ceramics is 2 × 10 −13 to 2.8 × 10 −13 cm 2 s −1 for rapid absorption and 5.9 × 10 −15 to 6.2 × 10 −15 cm s −1 for slow penetration. In the monocrystal, they are 4.5 × 10 −13 cm 2 s −1 and 2.5 × 10 −14 cm 2 s −1, respectively.