Abstract
A series of Tb3+, Eu3+-doped Sr2MgSi2O7 (SMSO) phosphors were synthesized by high temperature solid-state reaction. X-ray diffraction (XRD) patterns, Rietveld refinement, photoluminescence spectra (PL), and luminescence decay curves were utilized to characterize each sample’s properties. Intense green emission due to Tb3+ 5D4→7F5 transition was observed in the Tb3+ single-doped SMSO sample, and the corresponding concentration quenching mechanism was demonstrated to be a diople-diople interaction. A wide overlap between Tb3+ emission and Eu3+ excitationspectraresults in energy transfer from Tb3+ to Eu3+. This has been demonstrated by the emission spectra and decay curves of Tb3+ in SMSO:Tb3+, Eu3+ phosphors. Energy transfer mechanism was determined to be a quadrupole-quadrupole interaction. And critical distance of energy transfer from Tb3+ to Eu3+ ions is calculated to be 6.7 Å on the basis of concentration quenching method. Moreover, white light emission was generated via adjusting concentration ratio of Tb3+ and Eu3+ in SMSO:Tb3+, Eu3+ phosphors. All the results indicate that SMSO:Tb3+, Eu3+ is a promising single-component white light emitting phosphor.
Highlights
With the increasing seriousness of environmental problems and energy issues, white light emitting diodes (w-LEDs) have attract great attention in the lighting and display field due to their environmental friendliness, lower energy consumption, long lifetime, and extraordinary luminous efficiency compared with traditional incandescent or fluorescent lamps [1,2,3,4]
The second approach to generate white light is the assembly of a single LED chip with red, green, and blue phosphors or a single-phase phosphor, which is called phosphor converted white LEDs [6]
The results indicate that rare earth ions doped SMSO phosphors with space group of P-421m have a tetragonal structure
Summary
With the increasing seriousness of environmental problems and energy issues, white light emitting diodes (w-LEDs) have attract great attention in the lighting and display field due to their environmental friendliness, lower energy consumption, long lifetime, and extraordinary luminous efficiency compared with traditional incandescent or fluorescent lamps [1,2,3,4]. The second approach to generate white light is the assembly of a single LED chip with red, green, and blue phosphors or a single-phase phosphor, which is called phosphor converted white LEDs (pc-WLEDs) [6]. Nowadays, leading commercial w-LEDs are fabricated by a “blue (InGaN) LED chip + yellow (YAG:Ce3+ ) phosphor” [7,8] Inherent weaknesses such as high correlated color temperature (CCT > 7000 K) and poor color rendering index (CRI < 80) were caused by the absence of red component, which greatly limiting its application [9,10]. In addition to similar host materials, on onthethe other hand, energy transfer was observed in rare earthphosphors. Co-doped materials, other hand, energy transfer processprocess was observed in rare earth co-doped phosphors.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
