Sm3+ doped Bi4MgO4(PO4)2:crystal and optoelectronic investigation of the solution combustion derived bright orange emanating novel nanophosphor for SSLs

Autor: Sarita Khatkar, V.B. Taxak, R.K. Malik, Priya Phogat
Rok vydání: 2022
Předmět:
Zdroj: Materials Chemistry and Physics. 276:125389
ISSN: 0254-0584
DOI: 10.1016/j.matchemphys.2021.125389
Popis: Photoluminescent investigation and Rietveld refinement has been performed on trivalent samarium fused Bi4MgO4(PO4)2 -a novel nanophosphor series. The series from 0.5 mol% to 6 mol% dopant concentrations has been developed by means of a time efficacious path of solution combustion synthesis (SCS) fueled by urea. The X-ray powder diffraction patterns for complete Bi4(1-x)Sm4xMgO4(PO4)2 (x = 0.005–0.06) nanophosphor series being in accordance with that of pure host comply of phase purity. The arrangement in space group Pbca(61) and crystallization in orthorhombic cell of Sm3+ doped Bi4MgO4(PO4)2 is recognized by Rietveld refinement. The bivalent Mg ions as a part of [(PO4)2MgBi2O2]2- slabs are present alongside [Bi2O2]2+ planes in the unit cell. In host Bi4MgO4(PO4)2, the diffuse reflectance spectrum led calculations give an optical band-gap of 3.87 eV. The PL emission spectra mark 2 mol% as the optimal fluorescent composition and the emission intensity declines for further compositions. It is credited to concentration quenching phenomena due to dipole-dipole energy exchanges as observed by Dexter's theoretical model. The decay curves for Sm3+ doped phosphate-based nanophosphor bear bi-exponential decay behavior and hence, the average PL lifetime values derived are used in the Auzel's model to obtain the magnitude of radiative lifetime. The transmission electron microscopy operated at high -resolution (HRTEM) and field emission scanning electron microscopy (FE-SEM) inform about the polycrystalline and morphological behavior of the synthesized nanophosphor. The elemental purity of the sample is confirmed by the energy dispersive spectroscopy (EDS). The PL as well as decay curves are inspected to gain the quantum efficiencies and non-radiative rates for Sm3+ doped Bi4MgO4(PO4)2 nanophosphors. The analysis related to different parameters as well as chromaticity coordinates (x = 0.517, y = 0.480) and quantum efficiency (94%) espouse Bi3.92Sm0.08MgO4(PO4)2 for relevance in solid state lighting (SSLs) expedients.
Databáze: OpenAIRE
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