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In the present study, the Sr1−xAl2O4:Eux (x = 0.00, 0.01, 0.03, 0.05, 0.07, and 0.09) phosphor were synthesized by urea fuel combustion method at 580 °C temperature with very high brightness and long after glow. The structural studies carried out using XRD technique shows that the sample is single phased in nature and it gets crystallized into monoclinic phase with standard JCPDS 34-0379 card. The oxide formation was examined using FTIR technique. UV–Visible spectroscopy has been used to study the optical band gap of material, it's value in the current case, Sr1−xAl2O4:Eux (x = 0.05) is 3.78 eV. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM), confirm the formation of nano particle, with average particle size around 6–25 nm. The elemental composition was confirmed by using Energy Dispersive X-ray (EDX) technique. The photo-luminescence study revealed that it gives broad emission spectra using excitation wavelength λex = 365 nm. It is observed that the Sr1−xAl2O4:Eux (x = 0.05) phosphor give maximum emission intensity and it can be regulated as green (0.23, 0.49) emission with the colour temperature 3224 K, CRI 78, and colour purity 60.69%. The spectra are intense and lie in the visible range. The green lights can regulate the circadian rhythm through melatonin, and it is also suitable for green LED and other optoelectronic devices. The Sr1−xAl2O4:Eux (x = 0.00 and 0.05) phosphor behaves like eco-materials, because nano particles of Sr1−xAl2O4:Eux (x = 0.05) does not show antimicrobial activity. [ABSTRACT FROM AUTHOR]

Magnesium aluminates-based nanophosphors have been synthesised using the combustion reaction, where Nd3+ was varied from 0 to 0.075 molar concentrations. SrMgAl12O19:Nd3+ was studied for its morphology, structure, and photoluminescence (PL) properties. The XRD patterns from all samples were well correlated with the standard XRD pattern of SrAl12O19. Using energy dispersive X-ray spectroscopy (EDS) was demonstrated the presence of all the expected elements in the configuration. A scanning electron microscopy study revealed that the surface morphology changed as the concentration of Nd3+ increased. PL spectroscopic measurements of Nd3+ ions at 475 (cyan) and 575 (yellow) nm have been made by directly exciting them at 350 nm, corresponding to 4D3/2 + 4D5/2, ²P1/2, → 4F3/2 transitions, respectively. Results from colour coordinates provided by the (CIE 1931) indicate that the cyan blue emission colour originates from the synthesised phosphor. [ABSTRACT FROM AUTHOR]