Orthoborate LiSrY$_2$(BO$_3$)$_3$ Host with Low Concentration Quenching

LiSrY$_2$(BO$_3$)$_3$ is a recently explored host for observing lanthanide luminescence. This compound synthesized and activated with Tb$^{3+}$/Gd$^{3+}$ is described. Trivalent activators Tb$^{3+}$ and Gd$^{3+}$ occupy yttrium sites. Intense characteristic emission is observed for both these activators. In case of Gd$^{3+}$, both excitation and emission lines arise in f-f transitions. Photo luminescence emission is obtained in UV region. In case of Tb$^{3+}$, mild concentration quenching was observed above 10%. Prominent excitation of Tb$^{3+}$ is in form of a band arising in f–d type transition while emission comes from f–f transitions. Emission lifetimes are of the order of milliseconds, typical of forbidden f–f transitions.