Structural, photoluminescence and Judd-Ofelt analysis of red-emitting Eu3+ doped strontium hexa-aluminate nanophosphors for lighting application

Abstract

In this paper, the structural and luminescence properties of Eu 3+ - doped SrAl 12 O 19 nanophosphors are discussed. A series of SrAl 12 O 19 :xEu 3+ (x = 0.5, 1, 1.5, 2 and 2.5 mol %) nanophosphors were prepared using urea assisted-combustion synthesis method. The elemental and phase identification were performed by X-ray diffraction. The peak positions in the X-ray diffraction pattern have confirmed the formation of hexagonal structure. The vibration of oxide bonds and the formation of the molecules were confirmed from FTIR spectra. The surface morphology and particle size distribution are estimated using Field Emission-Scanning Electron Microscopy (FE-SEM), High Resolution-Transmission Electron Microscopy (HR-TEM). The optical properties of prepared nanophosphors series are studied using photoluminescence spectra and UV–visible spectra analysis. The refractive index of the optimized concentration of nanophosphor is estimated using Herve and Vandamme relation. Further, Judd-Ofelt analysis was performed on photoluminescence emission spectra. The potential application of synthesized nanophosphors in light-emitting devices (LED) is verified using photometry analysis on obtained emission spectra. The obtained CCT number confirmed that these phosphors are useful as a red color LED. • Red-emitting Eu 3+ -doped strontium hexa-aluminate nanophosphors are synthesized using combustion synthesis method. • The luminescence intensities of nanophosphors are strongly depending on Eu 3+ -concentration. • A detail Jud-Oflet analysis is performed on the nanophosphors. • The estimated CCT values showed that these phosphors are used for warm lighting application.