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采用凝胶-燃烧法制备了稀土Eu3+掺杂的LaMgAl11O19红色荧光粉的前驱粉末,在低于700℃退火处理时,得到非晶态样品,而高于850℃退火处理后为单一六方相结构LaMgAl11O19:Eu3+样品.SEM结果表明,该法制备的样品为颗粒分布均匀,粒径在200～400nm之间的超细粉末.通过激发光谱和发射光谱研究了Eu3+在LaMgAl11O19基质中的发光性能,结果显示,非晶态和晶态La1-xMgAl11O19:xEu3+样品都可发光,在613nm波长光的监测下所得荧光粉的激发光谱为一宽带和系列锐峰,其最强激发峰出现在蓝光465nm处,次强峰为394nm,表明该荧光粉与广泛使用的紫外和蓝光LED芯片的输出波长相匹配.在465nm波长光的激发下观察到超细LaMgAl11O19粉末中Eu3+的613nm(5D0→7F2)强的特征发射,且随着粉末逐渐成相5D0→7F2跃迁明显增强,说明LaMgAl11O19:Eu3+超细粉末可作为白光LED的红色补偿荧光粉.
The precursor powder of rare earth Eu3 + -doped LaMgAl11O19 red phosphor was prepared by gel-combustion method. When annealed at less than 700 ℃, the amorphous sample was obtained. When the temperature was above 850 ℃, the single-phase LaMgAl11O19 : Eu3 + sample.The SEM results show that the sample prepared by this method is an ultrafine powder with uniform particle size and particle size of 200 ~ 400nm.The emission properties of Eu3 + in LaMgAl11O19 matrix have been studied by excitation and emission spectra. The results show that , The amorphous and crystalline La1-xMgAl11O19: xEu3 + samples can all emit light. Under the monitoring of 613nm wavelength light, the excitation spectrum of the obtained phosphor is a broad band and a series of sharp peaks. The strongest excitation peak appears at 465nm of blue light, The strong peak was 394 nm, indicating that the phosphor matched the output wavelength of the widely used UV and blue LED chips. Strong emission of 613 nm (5D0 → 7F2) Eu3 + in ultrafine LaMgAl11O19 powder was observed at 465 nm wavelength , And the transition of the powder into phase 5D0 → 7F2 is obviously enhanced, indicating that LaMgAl11O19: Eu3 + ultra-fine powder can be used as red compensating phosphor for white LED.