Synthesis of SrAl₂O₄: Eu²⁺Dy³⁺phosphorescence nanosized powder by combustion method and its optical properties

SrAl2O4:Eu2+(,Dy3+) Nanosized Particles: Synthesis and Interpretation of Temperature-Dependent Optical Properties

“…After sintering under an Ar/H 2 atmosphere, the remaining Eu 3+ ions are completely reduced to Eu 2+ exhibiting a homogeneous very intense green emission upon irradiation of UV light ( Figure 5 [24,[27][28][29][30][31][32]. In the emission spectrum at room temperature only one broad band is observed located at 19 230 cm −1 (520 nm) with a full width at half maximum (FWHM) of 3 030 cm −1 .…”

“…Combustion synthesis, also called modified solid-state reaction, is applied for the preparation of highly crystalline compounds, for example, complex oxides such as aluminates [24], orthosilicates [25], and chromites [26] and has been successfully applied for the synthesis of SrAl 2 O 4 :Eu(,Dy) nanoparticles by several authors [24,[27][28][29][30][31][32]. The process consists of an exothermic redox reaction of an oxidizer, for example, metal nitrates and a reducing organic fuel, for example, urea [1].…”

Atomic layer deposition (ALD) of nanoscale coatings on SrAl2O4‐based phosphor powders to prevent aqueous degradation

“…Such changes to the electronic state of Eu 2+ lead to variability in the intensities of the excitation spectra at 322 and 360 nm as seen here. Reduced crystal quality or agglomeration has also been noted to redshift the emission spectra a few nanometers . Other possible contributing factors are changes in light absorption due to coating the powder with a wide bandgap material, altering light scattering due to coating the powder with a different refractive index material, and small changes in chemical composition due to chemical exposure and low‐temperature heating during the ALD process.…”

“…Reduced crystal quality or agglomeration has also been noted to redshift the emission spectra a few nanometers. 25,28 Other possible contributing factors are changes in light absorption due to coating the powder with a wide bandgap material, altering light scattering due to coating the powder with a different refractive index material, and small changes in chemical composition due to chemical exposure and low-temperature heating during the ALD process. However, overall, these data suggest that the ALD process does not significantly alter the phosphor material.…”

Preparing and testing the reliability of long-afterglow SrAl2O4:Eu2+, Dy3+ phosphor flexible films for temperature sensing

“…4,5 Recently, the SrAl 2 O 4 :Eu 2+ , Dy 3+ phosphor has received considerable research attention because of its stability and environmentally friendly properties, with various applications such as emergency signage, watch dials, luminous paints, traffic signs, and children's toys. [6][7][8][9][10] There are many techniques to manufacture strontium aluminate, such as sol-gel synthesis, 7 continuous solid-phase synthesis, 11 combustion, 12 and hightemperature solid-state method. 13 The high-temperature solidstate method synthesizes the phosphor with the highest crystallinity.…”