Luminous LaAlO₃:Dy³⁺ perovskite nanomaterials: Synthesis, structural, and luminescence characteristics for white light‐emitting diodes

Abstract

A single‐phase perovskite LaAlO3:Dy3+ phosphor was synthesized using a gel‐combustion method at 600°C utilization with hexamethylenetetramine as a fuel. Further calcination of the samples was carried out (800 and 1000°C) to investigate the resultant effect on the crystalline and luminescence behaviour. The crystal structure had a cubic unit cell (space group Pm3̅m) and was examined using the Rietveld refinement and X‐ray diffraction data. Additionally, Debye–Scherrer and Williamson–Hall equations were applied to determine other structural features. The particle size and morphology of phosphors were evaluated using transmission electron microscopy. Diffraction measurements were supported by the various metal–oxygen vibration modes studied with the help of Fourier transform infrared spectroscopy. Energy‐dispersive X‐ray analysis verified the chemical composition of synthesized sample. Luminescence spectra of the LaAlO3:Dy3+ phosphors exhibited intense bands for 4F9/2→6H15/2 (482 nm, bluish region) and 4F9/2→6H13/2 (574 nm, yellowish region) transitions. Commission Internationale de L'Eclairage and correlated colour temperature data confirmed the cool‐white emission of the samples under ultraviolet light excitation. The interesting and advantageous luminescence characteristics of LaAlO3:Dy3+ phosphors make them potential materials for white light‐emitting diodes.

Structural, morphological, and optical characteristics of Gd2Si2O7:Dy3+ nanophosphors for WLEDs

“…The blue emission corresponds to the magnetic dipole transition ( 4 F 9/2 → 6 H 15/2 ) that hardly varies with the crystal field around the Dy 3+ ion. Generally, the intensity ratio of these two types of dipole transitions accounts for the pertinent emission and local symmetry around Dy 3+ ions [42]. The evidence about the site symmetry around Dy 3+ ions was examined by considering the intensity ratio of yellow‐to‐blue (Y/B) emissions.…”

Crystallographic, morphological and photoluminescent investigations of Tb3+‐doped YAlO3 perovskites for lighting applications

“…Finally, the designated powdered materials at different sintered temperatures were characterized using various structural and spectroscopic studies in depth. An X-ray powder diffractometer (ULTIMA IV, Rigaku) was used to register the X-ray diffraction (XRD) patterns of the synthesized nanocrystals, that is, YAlO 3 :xTb 3+ (x = 0.01-0.08 mol) [32,33]. Crystallographic data of the synthesized nanocrystalline materials were obtained by Rietveld composed elements of the designated nanomaterials was obtained by Energy Dispersive X-ray Analysis (EDAX) spectral investigations.…”

Gadolinium-based Sm3+ activated GdSr2AlO5 nanophosphor: synthesis, crystallographic and opto-electronic analysis for warm wLEDs

“…2(b), in accordance with the Bragg diffraction hypothesis 2d sin q = nl. 37 The q-value decreased because the radius of the doped ions (Sm 3+ ) was bigger, which increased the value d-spacing, listed in Table 1. The GdSr 2 AlO 5 crystal lattice is composed of GdSrO 3+ and SrAlO 4 3+ layers, as displayed in Fig.…”