White-light emission from Li2Sr1−3x/2DyxSiO4 phosphors

• Published in: Applied physics. A, Materials science & processing Vol. 104; no. 1; pp. 83 - 88
• Main Authors: Sun, Xin-Yuan, Lin, Liang-Wu, Wang, Wen-Feng, Zhang, Jun-Cheng
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer-Verlag 01.07.2011; Springer
• Subjects: Characterization and Evaluation of Materials; Condensed Matter Physics; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Diffraction; Emission; Exact sciences and technology; Excitation; Machines; Manufacturing; Nanotechnology; Optical and Electronic Materials; Optical properties and condensed-matter spectroscopy and other interactions of matter with particles and radiation; Other solid inorganic materials; Phosphors; Photoluminescence; Physics; Physics and Astronomy; Processes; Silicon dioxide; Spectra; Surfaces and Interfaces; Thin Films; White light; Predominant Emission; Yellow Emission; Blue Chip; White Light; Resonance Energy Transfer; White light; Near ultraviolet radiation; Impurity density; Phosphors; Doping; Photoluminescence; Lithium Strontium Silicates Mixed; Excitation spectrum; Chromaticity; XRD; Dysprosium additions; Energy transfer
• ISSN: 0947-8396; 1432-0630
• DOI: 10.1007/s00339-011-6380-6

Li 2 Sr 1−3 x /2 Dy x SiO 4 phosphors were synthesized at 900°C in the normal atmosphere by a solid-state method. The synthesized phosphors were characterized by X-ray powder diffraction (XRD) and photoluminescence (PL) spectra. The photoluminescence excitation (PLE) spectra show excitation peaks ranging from 300 to 400 nm due to the 4 f -4 f transitions of Dy 3+ . This mercury-free excitation is useful for solid-state lighting and light-emitting diodes (LEDs). The predominant emission of Dy 3+ ions under 349 nm excitation is observed at 479 nm (blue) due to the 4 F 9/2 → 6 H 15/2 transitions and 572 nm (yellow) due to 4 F 9/2 → 6 H 13/2 transitions, respectively. The PL results reveal that the optimal concentration of the Dy 3+ ions in Li 2 Sr 1−3 x /2 Dy x SiO 4 phosphors is x =0.03 mol. The nature of the resonance energy transfer for the Dy 3+ ions is confirmed by Huang’s rule. Simulation of the white light excited by 349 nm near-ultraviolet (n-UV) light is also performed for its potential for white LEDs.