Optimizing the White Light Emission of Pr 3+ Activated SrCeO 3 Perovskite by Controlling the Excitation Wavelength for High CRI wLED Applications

• Published in: Journal of fluorescence
• Main Authors: Shilpa, C K, Abin Prasanth, M V, Jasira, S V, Veena, V P, Nissamudeen, K M
• Format: Journal Article
• Language: English
• Published: Netherlands 12.03.2024
• Subjects: Perovskite; wLED; Strontium cerate; Praseodymium
• ISSN: 1573-4994

The current research illustrates excitation energy-triggered photoluminescent characteristics of Pr ions in SrCeO providing a practical approach for developing high CRI wLED and its applications. SrCeO : xPr (x = 0, 0.005, 0.01, 0.02, 0.03 wt) perovskites synthesized by fuel excess gel combustion method generate high CRI (~98) for wLED applications. Crystalline phosphors with orthorhombic structures having space group Pnma were confirmed by XRD. The unit cell volume expansion occurred with an increase in Pr concentration was verified through the Rietveld refinement technique. Surface morphology, particle distribution, and size were observed via FE-SEM imaging, and detected a well-defined regular distorted spherical structure with average grain size 0.826 μm for Pr doped SrCeO . Elemental mapping and EDS analysis identified the uniform distribution and elemental purity of SrCeO : 0.01 Pr . Further, the molecular vibrations and modes were analyzed from the Raman spectrum. Moreover, the average particle size assessed via TEM analysis was found to be ~83.2 nm, consistent with XRD analysis. UV-visible absorption spectra for optical energy-band gap analysis showed a decrease in band gap energy with an increase in Pr concentration, realizing an effective energy transfer from Ce to Pr . PL measurements showed a huge variety of emission transitions, corresponding to excitations 290 nm, 321 nm, 373 nm, and 449 nm. The critical dopant concentration instigated by concentration quenching was 1 wt% Pr , ascribed to dipole-dipole interaction. The fluorescence lifetime of the optimal sample was 4.835 μs. Commission International de I'Eclairage (CIE) diagram exposes the white light emanation of SrCeO : Pr . Among which white light with high CRI (~98) and comparably low CCT (~6311 K) was obtained for SrCeO : 0.01 Pr at 373 nm excitation. The obtained results recommend that SrCeO : Pr perovskite as an efficient white phosphor for fabricating high-performance wLEDs.