Preparation and luminescence characteristics of lanthanide phosphors crystallized in phase separated glass

Abstract

Borosilicate glass crystallized into the borate phases GdBO₃:Tm³⁺ and GdF₃:Tm³⁺ was successfully prepared using the phase separation phenomenon. By optimizing its composition, the glass was ‘binodal’ phase separated into borate droplets inside a silica matrix. The lanthanide oxide and fluoride phosphors were restrictively created in the borate phase and an emission attributable to ¹D₂→³H₄ transition of Tm³⁺ was observed at 458 nm. Furthermore, the luminescent intensity of lanthanide trifluoride crystallized glass at low vibrational energy was 25% larger than that of oxide glass. Based on these results, glass phosphor appears to be a promising candidate for use as a new Gadolinium Neutron Capture Therapy material in cancerous tissue imaging.