Controlling luminescence colour through concentration of Dy3+ ions in LiLa1-xDyxP4O12 nanocrystals

Luminescence and excitation spectra of LiLa1-xDyxP4O12 nanocrystals are reported. In particular, the impact of dopant concentration on the luminescence properties of LiLa1-xDyxP4O12 nanocrystals was investigated. It was found that increase in Dy3+ concentration results in a strong quenching of luminescence. The mechanism of concentration quenching was discussed in terms of the Yokota-Tanimoto model. It is concluded that with increasing Dy3+ concentration, the donor-acceptor interaction leads to a significant concentration quenching resulting in nonexponential luminescence decay, whereas at a high concentration limit the donor-donor interaction becomes dominant and exponential decay is observed.