Luminescence of rare earth borosilicates with the stillwellite and related structures

摘要

By hydrothermal reactions it was possible to prepare well-crystallized borosilicates of composition La_(1-x-y)Ln_xLn'_yBSiO_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.