Study On Rare Earth Doped Lu₂ O₃ And LuAG Fluorescent Powders Prepared By Different Methods

Adopted different precipitants and titrating processing in co-precipitaion method, Lu2O3 powders were investigated. Mixed lutecium nitrate and europium nitrate solution, raw powders were obtained by normal and inverse titrating with ammonia. And the results were compared with powders precipitated by oxalate. Before and after calcining at 600oC and 1200oC, the powders were studied by means of DTA/TG and XRD. Lutecium oxalate lost crystallization water at 600oC and decomposed at 1200oC. The 265 nm, 300 nm absorption peaks and 613 nm, 626nm emission peaks were found in powders'spectra. The powders precipitated by inverse titrating with ammonia are uniform and average size is about 50 nm.LuAG powders are prepared by mixing solid oxides method and solution precipitation method. According to XRD and SEM results, powder particles which are synthesized by mixing oxides method are large, sharp and conglomerated. The most of raw oxides materials remained and some Lu₃Al₅O₁₂ were synthesized after calcining at 1200oC. Precipitations are produced by mixing Lu(NO₃)₃ and NaAlO2 solutions. Compared with solid method, particles are fine and smooth. The conglomerated powders are easily dispersed, and most of powders changed to LuAG phase after heating at 1200oC. The 603 nm, 613 nm emission peaks were found in powders'florescent spectra. It can be concluded that Eu3+ ions exist inLuAG: Eu powders prepared by precipitation methods.