Phase recognition, structural measurements and photoluminescence studies of reddish-orange-emissive YAlO3:Sm3+ perovskite nanophosphors for NUV energized WLEDs

Orthoaluminate perovskite-type YAlO3:xSm(3+) (x = 0.01 to 0.04 mol) nanocrystalline materials were synthesized successfully through solution combustion (SC) synthetic method. The prepared nanomaterials were characterised by means of X-ray diffraction (XRD) assisted Rietveld refinement, energy dispersive X-ray (EDX) spectroscopy, fourier-transform infrared (FTIR) spectroscopy and photoluminescence (PL) studies along with photometric parameters. The XRD pattern displayed that the diffraction lines were very well matched with JCPDS # 38-0222 and confirmed the phase purity of phosphors. Rietveld refinement of representative Y0.96AlO3:Sm-0.04(3+) phosphor showed that the prepared materials were crystallized into orthorhombic crystal system having space group pbnm (62), crystallographic constrains alpha = beta= gamma = 90 degrees , formula units (Z) = 4 and refinement parameters R-p = 5.65%, R-wp = 7.44 and chi(2) = 3.25 %. FTIR spectra indicated the presence of characteristics vibrations of functional groups in phosphors. Transmission electron microscopy (TEM) studies represents the presence of irregularly sized particles with spherical morphology. Crystallite size of the doped phosphors was estimated by Scherrer's formula followed by Williamson-Hall (W-H) plot. The strongest emission accredited to (4)G(5/2) -> H-6(7/2) transition was found to be at 604 nm, which accountable for their reddish-orange emission. The strongest excitation line was observed at 405 nm corresponding to H-6(5/2) -> P-6(3/2) intraconfigurational f-f transition which quantified that the phosphor could be proficiently applied in NUV (near visible ultraviolet) energized LED applications. (c) 2022 Elsevier B.V. All rights reserved.