Concentration quenching of the Eu³⁺-activated luminescence in some layered perovskites with two-dimensional arrangement

The quenching of Eu³⁺-emission in the layered perovskite compounds SrRE₂Al₂O₇, BaRE₂Ti₃O₁₀, RETa₃O₉ and RbRETa₂O₇ (RE = rare earths) with two-dimensional arrangement of rare earth ions was investigated. The highest luminescence intensity was observed in both tantalum compounds, RETa₃O₉ and RbRETa₂O₇. The concentration quenching found in these compounds can be explained by a percolation model with two-dimensional interactions between the Eu³⁺ sites in the host lattice. The energy transfer between the Eu³⁺ ions takes place by the multipole-multipole interaction among the nearest-neighbor sites in the rare earth sublattice.