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A Highly Luminous LiCaPO4:Eu2+ Phosphor Synthesized by a Solution Method Employing a Water-Soluble Phosphate Ester

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DOI: 10.4236/opj.2013.36A003    2,836 Downloads   4,719 Views   Citations


A LiCaPO4:Eu2+ phosphor with high photoluminescence was synthesized using a polymerizable complex (PC) method employing a water-soluble polyethylene glycol-conjugated phosphate ester (PEG-P). PEG-P could be obtained from a reaction among polyethylene glycol 300, phosphorus pentoxide, and pyrophosphoric acid. The PEG-P prepared was stable in an aqueous condition. A transparent solution and gel were obtained when the PEG-P was used as a source of P during the PC method, whereas the use of H3PO4 caused an undesirable precipitate. The LiCaPO4:Eu2+ obtained via the PC method employing the PEG-P showed higher emission intensity than those synthesized by a solid state reaction method and the PC method employing H3PO4. The high luminescence properties of the sample synthesized using the PEG-P may be attributed to high homogeneity of constituents in the sample.

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M. Kim, M. Kobayashi, H. Kato and M. Kakihana, "A Highly Luminous LiCaPO4:Eu2+ Phosphor Synthesized by a Solution Method Employing a Water-Soluble Phosphate Ester," Optics and Photonics Journal, Vol. 3 No. 6A, 2013, pp. 13-18. doi: 10.4236/opj.2013.36A003.


[1] S. H. M. Poort, W. Janssen and G. Blasse, “Optical Properties of Eu2+-Activated Orthosilicates and Orthophosphates,” Journal of Alloys and Compound, Vol. 260, No. 1-2, 1997, pp. 93-97.
[2] Y. S. Tang, S. F. Hu, C. C. Lin, N. C. Bagkar and R. S. Liu, “Thermally Stable Luminescence of KSrPO4:Eu2+ Phosphor for White Light UV Light-Emitting Diodes,” Applied Physics Letter, Vol. 90, No. 15, 2007, Article ID. 151108. 10.1063/1.2721846
[3] M. E. Hannah, A. P. Piquette, M. Anc, J. McKittrick, J. Talbot, J. Han and K. C. Mishra, “A Study of Blue Emitting Phosphors, ABPO4,” ECS Transaction, Vol. 41, No. 37, 2012, pp. 19-25.
[4] S. Zhang, Y. Huang and H. J. Seo, “The Spectroscopy and Structural Sites of Eu2+ Ions Doped KCaPO4 Phosphor,” Journal of Electrochemical Society, Vol. 157, No. 7, 2010, pp. J261-J266.
[5] S. D. More, M. N. Meshram, S. P. Wankhede, P. L. Muthal, S. M. Dhopte and S. V. Moharil, “Luminescence in LiCaPO4,” Physica B: Condensed Matter, Vol. 406, No. 5, 2011, pp. 1178-1181.
[6] M. Kakihana, “‘sol-gel’ Preparation of High Temperature Superconducting Oxides,” Journal of Sol-Gel Science and Technology, Vol. 6, No. 1, 1996, pp. 7-55.
[7] M. Kakihana, “Synthesis of High-Performance Ceramics Based on Polymerizable Complex Method,” Journal of Ceramic Society of Japan, Vol. 117, No. 1368, 2009, pp. 857-862.
[8] W. Weng, L. Huang and G. Han, “The Alkoxide Sol-Gel Process in the Calcium Phosphate System and Its Applications,” Applied Organometallic Chemistry, Vol. 13, No. 8, 1999, pp. 555-564.<555::AID-AOC913>3.0.CO;2-C
[9] J. R. Van Wazer and C. F. Callis, “Metal Complexing By Phosphates,” Chemical Reviews, Vol. 58, No. 6, 1958, pp. 1011-1046.
[10] F. Rashchi and J. A. Finch, “Polyphosphates: A review Their Chemistry and Application with Particular Reference to Mineral Processing,” Minerals Engineering, Vol. 13, No. 10-11, 2000, pp. 1019-1035.
[11] M. Kim, M. Kobayashi, H. Kato and M. Kakihana, “Enhancement of Luminescence Properties of a KSrPO4:Eu2+ Phosphor Prepared Using a Solution Method with a Water-Soluble Phosphate Oligomer,” Journal of Materials Chemistry C, Vol. 1, No. 36, 2013, pp. 5741-5746.
[12] D. J. Tracy and R. L. Reierson, “Commercial Synthesis of Monoalkyl Phosphates,” Journal of Surfactants and Detergents, Vol. 5, No. 2, 2002, pp. 169-172.
[13] P. Lightfoot, M. C. Pienkowski, P. G. Brucea, I. Abrahamd and E. Eh, “Synthesis and Structure of LiCaPO4, by Combined X-Ray and Neutron Powder Diffraction,” Journal of Materials Chemistry, Vol. 1, No. 6, 1991, pp. 1061-1063.
[14] C. Wan, J. Meng, F. Zhang, X. Deng and C. Yang, “An Efficient Blue-Emitting Phosphor LiCaPO4:Eu2+ for White LEDs,” Solid State Communications, Vol. 150, No. 31-32, 2010, pp. 1493-1495.
[15] J. K. Han, M. E. Hannah, A. Piquette, J. B. Talbot, K. C. Mishra and J. McKittrick, “Sol-Gel Synthesis of Single Phase, High Quantum Efficiency LiCaPO4:Eu2+ Phosphors,” ECS Journal of Solid State Science and Technology, Vol. 1, No. 1, 2012, pp. R37-R40.
[16] T. Goto, N. Wakamatsu, H. Kamemizu, M. Iijima, Y. Doi and Y. Moriwaki, “Sintering Mechanism of Hydroxyapatite by Addition of Lithium Phosphate,” Journal of Materials Science: Materials in Medicine, Vol. 2, No. 3, 1991, pp. 149-152.

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