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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