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以Y(NO_3)_3、Al(NO_3)_3、Ce(NO_3)_3为母盐,NH_4HCO_3为沉淀剂,在冲击射流反应器中合成YAG:Ce纳米粉体。使用SEM、XRD和荧光光谱仪,对前驱体和煅烧后的YAG:Ce荧光粉体进行表征,分析和讨论了加料速度、分散剂种类、分散剂用量、Ce掺杂量、煅烧温度的影响。在5~70mL/min加料速度范围内,得出10mL/min加料条件下合成的粉体荧光强度最强;选取的3种分散剂(NH_4)_2SO_4、乙二醇和聚乙二醇(PEG),都能提高粉体分散性,在同等添加量下,(NH4)2SO4的分散性最好,最佳加入量为金属母盐质量分数2.0%;考察了Ce的掺杂摩尔量x=1.0%~9.0%((Y1-xCex)3Al5O12),掺杂量为x=3.0%时荧光粉的发光强度最大。合成的前驱体在1000℃煅烧5h后能得到纯YAG相,粉体的结晶度和荧光强度均随着煅烧温度的升高而增强;在优化后的条件下合成粉体,经1000℃煅烧5h后,将粉体压制成坯体,经过1680℃真空烧结8h和在空气中1450℃退火2h,两面抛光后,制备出YAG:Ce透明陶瓷。
YAG: Ce nanopowders were synthesized in an impact jet reactor using Y (NO_3) _3, Al (NO_3) _3, Ce (NO_3) _3 as the parent salt and NH_4HCO_3 as precipitants. The precursors and calcined YAG: Ce phosphors were characterized by SEM, XRD and fluorescence spectroscopy. The effects of feed rate, dispersant type, dispersant dosage, Ce doping amount and calcination temperature were analyzed and discussed. The results showed that the fluorescence intensity of the synthesized powder was the highest under the condition of 5 mL / min and 5 mL / min, and the best dispersant was obtained under the condition of 10 mL / min. The three dispersants (NH 4) 2 SO 4, ethylene glycol and polyethylene glycol (PEG) (NH4) 2SO4 was the best dispersant, the optimal addition amount was 2.0% of the mass fraction of metal parent metal. The molar amount of Ce doping x = 1.0% ~ 9.0% ((Y1-xCex) 3Al5O12), the doping amount of x = 3.0% phosphor maximum luminous intensity. The synthesized YAG phase can be obtained after calcined at 1000 ℃ for 5h. The crystallinity and fluorescence intensity of the synthesized YAG phase both increase with the increase of calcination temperature. Under the optimum conditions, the powders are calcined at 1000 ℃ for 5h After the powder is pressed into a green body, after vacuum sintering at 1680 ° C. for 8 hours and annealing in air at 1450 ° C. for 2 hours, the YAG: Ce transparent ceramic is prepared after both surfaces are polished.