Abstract
A dedicated scanning transmission electron microscope equipped with energy dispersive X-ray spectrometer is used to study a distribution of Mo ions in a phase-separated glass with a composition of 13Na
2O.49B
2O
3.38SiO
2 containing 1 mol% molybdenum oxide. Characteristic X-ray spectra at a high spacial resolution (
∼100
A
̊
) revealed that concentrations of Mo ions in a droplet, a matrix and an interface are 0.3, 1.3 and 4.1 (wt%), respectively. Whiskers of MoO
2 crystals are often observed at the interface, where Mo ions are enriched.