A crystal chemical approach to tuning of emission properties in rare earth doped ternary niobates
Abstract
The photoluminescence (PL) properties of two Dy3+ doped ternary niobates, LaNbO4 and CaNb2O6 with fergusonite and columbite structures, respectively are investigated and compared. When the emission line corresponding to electric dipole transition of Dy3+ at 574 nm is monitored, an intense band due to host excitation is observed in both LaNbO4:Dy3+ CaNb2O6:Dy3+ systems indicating host-to-activator energy transfer. The presence of a host emission band at 250–300 nm range under 574 nm excitation indicates that the energy transfer is incomplete. The presence of host lattice emission plays an important role in determining the intensity and spectral response of the phosphor compositions.