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通过溶胶凝胶法制备Lu2SiO5(LSO)干凝胶前驱体,对其进行综合热分析(IG-DSC),TG曲线在400℃后趋于平缓,DSC曲线在402.8℃和1049.9℃的放热峰分别对应着LSO粉体的结晶开始温度与晶型转变点.干凝胶在900℃、1000℃、1100℃、1200℃下煅烧2h,X射线衍射图谱(XRD)显示,900℃煅烧2h,产物结晶不完全,还存在大量的非晶相,但已有A-LSO相的特征衍射峰出现;1000℃煅烧2h,粉体完全结晶生成A-LSO相,1100℃煅烧后粉体呈B-ISO相,晶型转变点为1050℃左右,结果与DSC曲线中1049.9℃处的焓变峰值相对应.A、B两相颗粒形貌存在明显差别,粉体颗粒尺寸都在400～500 nm.粉体发射光谱在595 nm,617 nm,707 nm处存在发射峰,分别对应Eu3+的5D0→7F1,5D0→7F2,5D0→7F4跃迁,发光强度随着Eu3+掺杂浓度升高先增强后降低,掺杂浓度为5％左右时,发光强度达到最大值.

Lu2SiO5 (LSO) dried gel precursors were prepared by sol-gel method,which was subjected to thermal analysis.The TG curves were stable after 400 ℃.The exothermic peaks of the DSC curve at 402.8 ℃ and 1049.9 ℃,respectively correspond to the initial crystallization temperature of LSO powder and the phase transition temperature.The dried gel was calcined at 900 ℃,1000 ℃,1100 ℃ and 1200 ℃ for 2 h.The XRD shown that after calcination at 900 ℃ for 2 h,the product was not completely crystallized and amorphous phase also existed,but the characteristic diffraction peak of A-LSO phase had appeared.After calcination at 1000 ℃ for 2 h,the powders completely crystallized as A-LSO phase.After calcination at 1100 ℃ for 2 h,the A-LSO phase transformed to B-LSO phase,and the crystal transformation temperature was about 1050 ℃,which corresponded to the exothermic peak at 1049.9 ℃ in DSC curve.There were significant differences in the morphology of A-LSO and B-LSO.The particle size were both in 400-500 nm.The emission peaks located at 595 nm,617 nm,707 nm correspond to the 5D0→TF1,SD0→7F2,5D0→7F4 transition of Eu3+ respectively.The luminescence intensity was increased first and then decreased with the increase of Eu3+ doping concentration.The optimum doping concentration is 5％ mol.