Luminescence of rare earth borosilicates with the stillwellite and related structures

Abstract

By hydrothermal reactions it was possible to prepare well-crystallized borosilicates of composition La 1 − x − y Ln x Ln′ y BSiO 5 with the trigonal stillwellite structure. Ln = Eu 3+ and Tb 3+ produce compounds with only weak luminescence. Compounds with Ln = Ce 3+ are strong UV phosphors with peak intensity at x = 0.08 and abrupt concentration quenching at x = 0.10. Compounds with Ln = Ce 3+ and Ln′ = Tb 3+ exhibit effective Ce 3+ → Tb 3+ coactivation and strong green luminescence. This family of borosilicates appears to be useful phosphor hosts, aside from the necessity of non-traditional synthesis.