Abstract
Phosphors based on strontium aluminates activated by Eu2+ ions with various Al/Sr ratios were synthesized by a traditional high-temperature solid-state method. The influences of Al/Sr ratio, sintering temperature, the doping concentration of europium ions on structural transformation and luminescent properties of the phosphors were studied. The quenching and luminescent mechanisms were also discussed. The optimum synthetic temperature and time are about 1350 °C and 3.5 h derived from the analysis and experiment. At the range of Al/Sr ratio from 1.5 to 4.0, there are only three crystal structures, Sr3Al2O6 (1.5) cubic structure, SrAl2O4 (2.0–3.0) monoclinic crystal system and Sr4Al14O25 (3.0–4.0) orthorhombic crystal system. Under UV light excitation, the emission peaks gradually generate blueshift from 510 nm of Sr3Al2O6:Eu2+ phosphor to 483 nm of Sr4Al14O25:Eu2+ phosphor and the two emission peaks are originated from 4f 65d 1 to 4f 7 intrinsic transition of Eu2+ ions. The best green and blue luminescent samples are SrAl2O4:Eu2+ and Sr4Al14O25:Eu2+, and their color purity is 0.6667 and 0.8229, respectively. The best doping amount of Eu2+ is 0.5 at.%, and the concentration quenching mechanism of Eu2+ ions in SrAl2O4:Eu2+ and Sr4Al14O25:Eu2+ phosphors can be ascribed to the dipole–dipole interaction. There are three types of 6, 7 and 10 coordination numbers around Sr2+(Eu2+) ion, which forms three types of polyhedras, resulting in generating three excitation peaks at 334, 368 and 430 nm corresponding to the 6, 7 and 10 coordination polyhedral. The relation between energy level splitting and coordination number can be expressed as E 6 (6-coordination) > E 7 (7-coordination) > E 10 (10-coordination) in aluminate phosphor, and the splitting width of 6, 7 and 10 coordination numbers is 1.29, 0.78 and 0.31 eV, respectively. The coordination field only affects the energy top of crystal field splitting, and the larger the coordination number is, the lower the energy level top of crystal field splitting in Sr4Al14O25:Eu2+ phosphor is.
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References
Zhang X, Wang J, Huang L, Pan F, Chen Y, Lei B, Wu M (2015) Tunable luminescent properties and concentration-dependent, site-preferable distribution of Eu2+ ions in silicate glass for white LEDs applications. ACS Appl Mater Interfaces 7:10044–10054
Palilla FC, Levine AK, Tomkus MR (1968) Fluorescent properties of alkaline earth aluminates of the type MAl2O4 activated by divalent europium. J Electrochem Soc 115:642–644
Matsuzawa T, Aoki Y, Takeuchi N, Murayama Y (1996) A new long phosphorescent phosphor with high brightness, SrAl2O4:Eu2+, Dy3+. J Electrochem Soc 143:2670–2673
Feng X, Feng W, Wang K (2015) Experimental and theoretical spectroscopic study of praseodymium(III) doped strontium aluminate phosphors. J Alloys Compd 628:343–346
Van den Eeckhout K, Smet PF, Poelman D (2010) Persistent luminescence in Eu2+-doped compounds: a review. Materials 3:2536–2566
Li YQ, Hintzen HT (2006) Luminescence properties of Eu2+-doped MAl2−x Si x O4−x N x (M = Ca, Sr, Ba) conversion phosphor for white LED applications. J Electrochem Soc 153:278–282
Lin Y, Tang Z, Zhang Z (2001) Preparation of long-afterglow Sr4Al14O25-based luminescent material and its optical properties. Mater Lett 51:14–18
Alahraché S, Al Saghir K, Chenu S, Veron E, de Sousa Meneses D, Becerro AI, Cusso F (2013) Perfectly transparent Sr3Al2O6 polycrystalline ceramic elaborated from glass crystallization. Chem Mater 25:4017–4024
Gao HM, Yan FY, He L (2015) Synthesis and luminescence property of Sr3Al2O6:Eu3+ red phosphor prepared by co-precipitation technique. Adv Mater Res 1096:486–491
Page P, Ghildiyal R, Murthy KVR (2006) Synthesis, characterization and luminescence of Sr3Al2O6 phosphor with trivalent rare earth dopant. Mater Res Bull 41:1854–1860
Zhang P, Li L, Xu M, Liu L (2008) The new red luminescent Sr3Al2O6:Eu2+ phosphor powders synthesized via sol–gel route by microwave-assisted. J Alloys Compd 456:216–219
Zhong R, Zhang J, Zhang X, Lu S, X-j Wang (2006) Red phosphorescence in Sr4Al14O25: Cr3+, Eu2+, Dy3+ through persistent energy transfer. Appl Phys Lett 88:201916
Dutczak D, Ronda C, Justel T, Meijerink A (2014) Anomalous trapped exciton and d–f emission in Sr4Al14O25:Eu2+. J Phys Chem A 118:1617–1621
Garcia CR, Oliva J, Romero MT, Diaz-Torres LA (2016) Enhancing the photocatalytic activity of Sr4Al14O25:Eu2+, Dy3+ persistent phosphors by codoping with Bi3+ ions. Photochem Photobiol 92:231–237
Chang C, Li W, Huang X, Wang Z, Chen X, Qian X, Mao D (2010) Photoluminescence and afterglow behavior of Eu2+, Dy3+ and Eu3+, Dy3+ in Sr3Al2O6 matrix. J Lumin 130:347–350
Inan Akmehmet G, Šturm S, Bocher L, Kociak M, Ambrožič B, Ow-Yang CW (2016) Structure and luminescence in long persistence Eu, Dy, and B codoped strontium aluminate phosphors: the boron effect. J Am Ceram Soc 99:2175–2180
Zhang J, Ge M (2011) Effecting factors of the emission spectral characteristics of rare-earth strontium aluminate for anti-counterfeiting application. J Lumin 131:1765–1769
Kshatri DS, Khare A (2014) Characterization and optical properties of Dy3+ doped nanocrystalline SrAl2O4:Eu2+ phosphor. J Alloys Compd 588:488–495
Sahu IP, Bisen DP, Brahme N, Tamrakar RK (2016) Luminescence behavior of europium activated strontium aluminate phosphors by solid state reaction method. J Mater Sci Mater Electron 27:3443–3455
Mishra SB, Mishra AK, Revaprasadu N, Hillie KT, Steyn WV, Coetsee E, Swart HC (2009) Strontium aluminate/polymer composites: morphology, luminescent properties, and durability. J Appl Polym Sci 112:3347–3354
Dutczak D, Jüstel T, Ronda C, Meijerink A (2015) Eu2+ luminescence in strontium aluminates. Phys Chem Chem Phys 17:15236–15249
Ma W, Wan FR, Long Y, Shang CJ (2003) Relation between luminescence and granularity of SrAl2O4: Eu, Dy. Faguang Xuebao Chin J Lumin 24:95–99
Akiyama M, Xu CN, Liu Y, Nonaka K, Watanabe T (2002) Influence of Eu, Dy co-doped strontium aluminate composition on mechanoluminescence intensity. J Lumin 97:13–18
Aitasalo T, Dereń P, Hölsä J, Jungner H, Krupa JC, Lastusaari M, Stręk W (2003) Persistent luminescence phenomena in materials doped with rare earth ions. J Solid State Chem 171:114–122
Luo X, Cao W, Xiao Z (2006) Investigation on the distribution of rare earth ions in strontium aluminate phosphors. J Alloys Compd 416:250–255
Xingdong LÜ, Wangen SHU (2007) Roles of crystal defects in the persistent luminescence of Eu2+, Dy3+ co-doped strontium aluminate based phosphors. Rare Met 26:305–310
Clabau F, Rocquefelte X, Jobic S, Deniard P, Whangbo MH, Garcia A, Le Mercier T (2005) Mechanism of phosphorescence appropriate for the long-lasting phosphors Eu2+-doped SrAl2O4 with codopants Dy3+ and B3+. Chem Mater 17:3904–3912
Shaheen SE, Jabbour GE, Morrell MM, Kawabe Y, Kippelen B, Peyghambarian N, Armstrong NR (1998) Bright blue organic light-emitting diode with improved color purity using a LiF/Al cathode. J Appl Phys 84:2324–2327
Wondraczek L, Krolikowski S, Nass P (2013) Europium partitioning, luminescence re-absorption and quantum efficiency in (Sr, Ca) åkermanite—feldspar bi-phasic glass ceramics. J Mater Chem C 1:4078–4086
Ho CL, Wong WY, Gao ZQ, Chen CH, Cheah KW, Yao B, Yu XM (2008) Red-light-emitting iridium complexes with hole-transporting 9-arylcarbazole moieties for electrophosphorescence efficiency/color purity trade-off optimization. Adv Func Mater 18:319–331
Feng J, Li F, Gao Cheng G, Xie W, Liu S (2002) Improvement of efficiency and color purity utilizing two-step energy transfer for red organic light-emitting devices. Appl Phys Lett 81:2935–2937
Sugar J, Spector N (1974) Spectrum and energy levels of doubly ionized europium (Eu III). JOSA 64:1484–1497
Hölsä J, Laamanen T, Lastusaari M, Niittykoski J, Novák P (2009) Electronic structure of the SrAl2O4:Eu2+ persistent luminescence material. J Rare Earths 27:550–554
Chandra BP, Sonwane VD, Haldar BK, Pandey S (2011) Mechanoluminescence glow curves of rare-earth doped strontium aluminate phosphors. Opt Mater 33:444–451
Luan L, Guo CF, Huang DX (2009) Effect of Al/Sr ratio on properties of strontium aluminate long lasting phosphor. J Inorg Mater 24:53–56
Minquan W, Wang D, Guanglie L (1998) Research on fluorescence spectra and structure of single-phase 4SrO·7Al2O3:Eu2+ phosphor prepared by solid-state reaction method. Mater Sci Eng B 57:18–23
Li X, Budai JD, Liu F, Chen YS, Howe JY, Sun C, Pan Z (2015) Crystal structures and optical properties of new quaternary strontium europium aluminate luminescent nanoribbons. J Mater Chem C 3:778–788
Komatsu K, Nakamura A, Kato A, OhshioS Saitoh H (2015) Blue phosphor synthesized with Eu-containing strontium aluminate by reaction on single crystalline magnesia. Phys Status Solidi (c) 12:809–813
Kaya SY, Karacaoglu E, Karasu B (2012) Effect of Al/Sr ratio on the luminescence properties of SrAl2O4:Eu2+, Dy3+ phosphors. Ceram Int 38:3701–3706
Wu S, Zhang S, Liu Y, Yang J (2007) The organic ligands coordinated long afterglow phosphor. Mater Lett 61:3185–3188
Kshatri DS, Khare A (2014) Optical properties of rare earth doped strontium aluminate (SAO) phosphors: a review. Opt Spectrosc 117:769–783
Sharma SK, Pitale SS, Malik MM, Dubey RN, Qureshi MS (2008) Synthesis and detailed kinetic analysis of Sr4Al14O25:Eu2+ phosphor under black light irradiation. Radiat Eff Defects Solids 163:767–777
Yoon S, Bierwagen J, Trottmann M, Walfort B, Gartmann N, Weidenkaff A, Pokrant S (2015) The influence of boric acid on improved persistent luminescence and thermal oxidation resistance of SrAl2O4:Eu2+. J Lumin 167:126–131
Rojas-Hernandez RE, Rodriguez MA, Rubio-Marcos F, Serrano A, Fernandez JF (2015) Designing nanostructured strontium aluminate particles with high luminescence properties. J Mater Chem C 3:1268–1276
Acknowledgements
This work was supported by the Projects of the National Natural Science foundation of China (Nos. 51602027, 61307118), of Jilin Science and Technology Bureau (No. 201201117), of Changchun Science and Technology Bureau (No. 2013045).
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Zhang, B., Liu, Q., Yan, W. et al. Relation between structure conversion and spectra-tuning properties of Eu2+-doped strontium aluminate phosphor. J Mater Sci 52, 8188–8199 (2017). https://doi.org/10.1007/s10853-017-1027-4
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DOI: https://doi.org/10.1007/s10853-017-1027-4