Luminescence in Sr₄Al₁₄O₂₅:Ce³⁺ aluminate phosphor

Abstract

Cerium-doped Sr4 Al14 O25 phosphor is prepared using a single-step combustion synthesis and its X-ray diffraction (XRD), scanning electron microscopy (SEM), photoluminescence (PL) and thermoluminescence (TL) properties are characterized. XRD reveals the formation of the desired phase in the prepared sample. SEM micrographs of the prepared Sr4 Al14 O25 phosphor show that the particle size is 10 µm. The prepared Sr4 Al14 O25 , along with Sr4 Al14 O25 :Cex (x = 0.5-5 mol%) shows a PL emission peak at 314 nm under UV excitation of 262 nm wavelength due to 5d → 4f transition. The phosphor is suitable for higher concentrations of Ce ions. The TL glow peak reveals three clearly visible distinct peaks at temperatures around 130, 231 and 336ºC. The three peaks are separated by deconvolution and kinetic parameters calculated using Chen's peak shape method. The calculation shows that the reaction follows second-order kinetics with activation energy (E) values of 0.52, 0.81 and 1.12 eV, and frequency factor (s) values of 5.58 × 10(5) , 4.53 × 10(7) and 4.57 × 10(8) s(-1) for the three individual peaks.

First-principles calculations to identify key native point defects in Sr4Al14O25

“…Many experimental investigations reported various luminescent properties of Sr 4 Al 14 O 25 when doped with transition metals or lanthanides. 1,7,9,13,19 Indeed, this doped material may appear as appealing for industrial lighting applications. Among the most promising discoveries is the red luminescence of Sr 4 Al 14 O 25 :Mn 4+ , 1 possibly used as a key ingredient to improve the color rendering of the white light-emitting diode (WLED) technologies based on the InGaN/YAG:Ce 3+ approach.…”

“…[1][2][3][4][5][6][7] In contrast, Ce 3+ dopants induce a blue-green emission. 8,9 Moreover, Mn 4+ ,Tb 3+ co-doped Sr 4 Al 14 O 25 is a thermographic material for temperature imaging, as the emission color strongly changes due to the thermal quenching of the Mn 4+ emission. 10 Eu 2+ , Eu 3+ co-doped Sr 4 Al 14 O 25 also shows important color changes from 298 to 523 K. 11 In addition, a blue-green long lasting luminescence can be triggered by the co-insertion of Eu 2+ and Dy 3+ cations, 12,13 that may transform into a red luminescence if Cr 3+ cations are added 14,15 Conversely, a blue afterglow is observed for Tb 3+ dopants only.…”

Design, Synthesis, and Characterization of a Novel Blue-Green Long Afterglow BaYAl3O7:Eu2+, Nd3+ Phosphor and Its Anti-Counterfeiting Application

“…For example, CaAl 2 O 4 :Eu 2+ , Nd 3+ (blue), Sr 2 MgSi 2 O 7 :Eu 2+ , Dy 3+ (blue), SrAl 2 O 4 :Eu 2+ , Dy 3+ (green), Ca 2 BO 3 Cl:Eu 2+ , Dy 3+ (yellow), Ca 3 Si 2 O 7 :Eu 2+ , Sm 3+ /Tm 3+ (orange), CaS:Eu 2+ , Tm 3+ (red), Sr 5 (PO 4 ) 3 Cl:Eu 2+ , Nd 3+ (NIR) [9,[16][17][18][19][20][21], etc. Furthermore, various synthetic processes, including sol-gel, combustion, and co-precipitation, have been used to synthesize these long afterglow luminescent materials [22][23][24][25]. Among these, the combustion method is simple to use, appropriate for high-volume and low-cost preparation, and permits the synthesis of nanoparticles with controlled shape and particle size at lower temperatures [11,26].…”