Photoluminescence of praseodymium-doped Srn+1+TinO3n+1 (n=1, 2, ∞)

Perovskite-related compounds, Srn+1TinO3n+1: Pr3+ (n = 1, 2, infinity), were prepared by a Pechini-type polymerizable complex, method using a citric metal complex and their photoluminescence properties were investigated. The photoluminescence spectra of these compounds show distinct peaks at approximately 490 nm and/or 610 nm, which correspond to the intra-4f transitions from the excited state P-3(0) to the ground state H-3(4), D-1(2) to H-3(4) of Pr3+, respectively. The excitation process is consistent with the transition between the valence band and the conduction band in host materials. The most intense red emission was observed for the compound with n = 2 (Sr3Ti2O7: Pr3+), following by the compounds, n = I and it = infinity. The differences in luminescent properties among the compounds originate from the structural dependence of the energy transfer from the host to the activator Pr3+, and the site symmetry of Pr3+.