Photoluminescence and electrical properties of Eu3+-doped Na0.5Bi4.5Ti4O15-based ferroelectrics under blue light excitation

Ho‐doped SrBi2Nb2O9 multifunctional ceramics with bright green emission and good electrical properties

“…The excitation peaks located at 418, 450, 468, and 486 nm attributed to the typical f ‐ f electronic transition from 5 I 8 ground state to the 5 G 5 , 5 G 6 , 5 K 8 + 5 F 2 , and 5 F 3 excited states as refers to the energy level diagram for Ho 3+ ions, respectively . The remarkably strong excitation peak located at 450 nm which around the emission wavelength of commercial blue light‐emitting diodes (LEDs) chips (450–470 nm), indicates that samples acted as a potential blue light exciting phosphor . Under the blue light excitation, the PL spectra exhibits two bands located at 545 and 647 nm.…”

“…With Ho 3+ increasing, the intensity increases at first and then decreases remarkably, reaches the maximum at x = 0.004. This behavior can be owing to the concentration quenching effect . The concentration‐quenching is closely related to the bismuth layer perovskite structure and caused by the energy transfer from one to another activator ion until the energy is depleted.…”

“…When Ho 3+ dopants entered into the BLESs lattice, Ho 3+ preferentially entered into the (A m −1 B m O 3 m +1 ) 2− layers and occurred the energy transfer primarily, rather than the (Bi 2 O 2 ) 2+ layers. Thus, nonradiative energy transfer between nearby Ho 3+ ions exceeds the critical value, which always lead to the high quenching concentrations and thus results in the decrease of the luminescence intensity when dopants reach certain content .…”

On the Lanthanide Effect on Functional Properties of 0.94Na0.5Bi0.5TiO3-0.06BaTiO3 Ceramic

“…At 360 nm excitation, a prominent red emission peak at 607 nm, which is associated with the 5 D 0 → 7 F 2 transition, dominates the PL spectra of the BNT-BT-Eu 3+ . The transitions 5 D 0 → 7 F 1 , 5 D 0 → 7 F 3 , and 5 D 0 → 7 F 4 are represented by the comparatively feeble emissions with peaks at 576, 644, and 704 nm, respectively [66].…”