Exploration of zinc borophosphate glasses as dispersion media for SiAlON phosphors

Abstract

Ca-α-SiAlON:Eu 2+ oxynitride phosphors are typical luminescent materials with high thermal tolerances. A series of zinc borophosphate glass samples (ZnO-B 2 O 3 -P 2 O 5 ) were prepared to investigate their ability to disperse Ca-α-SiAlON:Eu 2+ phosphor powders and to obtain phosphor-in-glass (PiG). PiG was prepared with SiAlON and zinc borophosphate glass through a melting process, and seven types of PiGs were successfully obtained without obvious degradation of SiAlON. In particular, PiGs prepared from 30ZnO-40B 2 O 3 -30P 2 O 5 and 60ZnO-30B 2 O 3 -10P 2 O 5 (mol%) glasses showed the highest quantum efficiency (QE). The glass structures of the mother glasses were investigated by nuclear magnetic resonance spectroscopy (NMR) and Raman spectroscopy; it was important to reduce the Q 0 species of PO 4 units and 4-coordinate boron for a high QE. From the X-ray diffraction (XRD) and scanning electron microscopy (SEM) images, it was established that ZnAl 2 O 4 was formed around the SiAlON powders in PiG composed of the 60ZnO-30B 2 O 3 -10P 2 O 5 (mol%) glass. K E Y W O R D S crystallization, glass structure, phosphor-in-glass, SiAlON phosphor, zinc borophosphate glass