On the sol–gel fabrication and characterization of undoped and cerium-doped Sr4Al14O25

Enhancing photoluminescence properties of Mn4+‐activated Sr4−xBaxAl14O25 red phosphors for plant cultivation LEDs

“…Additionally, the similar peak of 1382 cm −1 should be caused by the vibrations of Al-O band according to the previous literature. 45 Quite obviously, the regions of 1082 to 1268 cm −1 is gradually increased with a peak at 1183 cm −1 with the increase of Ba 2+ doping concentration, that could be derived to be due to the formation of the Ba-O bond. It also can be demonstrated that the Ba 2+ is successful incorporated to the Sr 4 Al 14 O 25 host.…”

“…It is can found that the peaks of all samples at 3441 and 1638 cm −1 can be attributed to the stretching vibrations and bending vibrations of O‐H band in the water molecules. Additionally, the similar peak of 1382 cm −1 should be caused by the vibrations of Al–O band according to the previous literature . Quite obviously, the regions of 1082 to 1268 cm −1 is gradually increased with a peak at 1183 cm −1 with the increase of Ba 2+ doping concentration, that could be derived to be due to the formation of the Ba–O bond.…”

“…General speaking, the IR peaks in the range from 400 to 1000 cm −1 that are assigned to the stretching vibration of metal‐oxide bond in inorganic metal network structure . Thus, some shoulder peak can be attributed the Sr‐O and Al‐O stretching and bending vibrations such the peaks of 901 and 748 cm −1 …”

“…46 Thus, some shoulder peak can be attributed the Sr-O and Al-O stretching and bending vibrations such the peaks of 901 and 748 cm −1 . 45 Diffuse reflectance spectra can not only reflect the excitation spectra of phosphors but also further calculate the band gap to explore its luminescence mechanism. The DR spectra of Sr 4 Al 14 O 25 host material, SAO:0.01Mn 4+ , 1.4H 3 BO 3 and SBAO:0.01Mn 4+ , 1.4H 3 BO 3 phosphors are characterized in the Figure 7A.…”

Synthesis, luminescence and persistent luminescence of europium-doped strontium aluminates

“…This observation shows that also the cooling speed can have a dramatic effect on the phase purity of the sample. Misevicius et al [89] prepared S4A7:Ce 3+ particles via the sol-gel method followed by a post-annealing step at 1573 K. The precursor particles agglomerated during the annealing process. Interestingly, when boric acid was used as flux in the reaction mixture, hexagonal plates (ca 5 μm diameter) with well-defined edges were obtained.…”