LAUSR

In this paper, Pr3+ doped Na0.25K0.25Bi2.5Nb2O9 (NKBN-xPr3+) ceramics were successfully prepared via a conventional solid-state reaction process. The structural, dielectric, and piezoelectric properties as well as photoluminescence performance of the samples were systemically studied. All the ceramic samples possessed a pure two-layered bismuth layer-structure with the A21am space group. Raman spectra revealed that the doped Pr3+ ions mainly replaced Bi3+ at the A-sites in the pseudo-perovskite layers. With increasing Pr3+ concentration, the Curie temperature and the maximum dielectric constant of the samples decreased, while the piezoelectric constant d33 increased from 15 pC/N for x = 0 to 21 pC/N for x = 0.01. Addition, d33 remained almost unchanged for all samples when the annealing temperature was lower than 450 °C. Under excitation with 452 nm light, the obtained samples exhibited a typical emission of Pr3+ ions, with the strongest red emission peak centered at 609 nm. The corresponding color tone of the ceramics shifted from red-orange to orange-yellow with increasing Pr3+ doping. The thermal quenching behavior of the photoluminescence of the x = 0.01 sample was also investigated in detail, and the thermal quenching activation energy was calculated to be 0.4473 eV. Our study indicated that NKBN-xPr3+ ceramics may have potential applications in multi-functional devices.