Dual-emitting phosphor Sr4Al14O25:Eu2+/3+ prepared in air for ratiometric temperature sensing

Luminescent Materials Based on Aluminates: A Review

“…The site-dependent emission of Eu 2þ ions can be used for optical thermometry. [129,130] 490 nm emission of Sr 2 Al 6 O 11 : Eu 2þ with nUV excitation can also be useful for LED lamps based on nUV chips. [131] The Afterglow of Sr 2 Al 6 O 11 :Eu 2þ can be handy for reducing flicker.…”

Tetrahedrally coordinated rigid crystal structure enables partial self-reduction of mixed-valence europium for optical thermometric application

“…45,46 It was proposed by Su et al 43 that the necessary conditions determining whether self-reduction occurs in the oxidizing atmosphere are: (a) the compounds having an appropriate structure with the tetrahedral anion groups (BO 4 , SO 4 , PO 4 , SiO 4 , or AlO 4 ) with no oxidizing ions; (b) the divalent cation of the host being replaced by Eu 3+ ions and the substituted cation possessing a similar radius as the Eu 2+ ions. [47][48][49] To construct a Eu 2+ /Eu 3+ couple co-activated ratiometric thermometer, herein, we focused on the CaBPO 5 compound. We believe that the Eu 3+ ion is capable of self-reduction to Eu 2+ in this compound under oxidizing atmosphere as it exactly meets the self-reduction conditions from a crystal structure point of view.…”

“…45,46 It was proposed by Su et al 43 that the necessary conditions determining whether self-reduction occurs in the oxidizing atmosphere are: (a) the compounds having an appropriate structure with the tetrahedral anion groups (BO 4 , SO 4 , PO 4 , SiO 4 , or AlO 4 ) with no oxidizing ions; (b) the divalent cation of the host being replaced by Eu 3+ ions and the substituted cation possessing a similar radius as the Eu 2+ ions. 47–49…”

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

“…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. 16 Also, unintentional strontium and oxygen vacancies have been reported to possibly play a role in the luminescent phenomena.…”