SrSi2O2N2∶Eu2+荧光粉的制备及性能研究

以SrCO3,Si3N4,Eu2O3为原料,在N2气氛下,采用自还原高温固相法制备了SrSi2O2N2:Eu2+荧光粉。研究了该荧光粉的物相结构、发光性能和晶体形貌,同时对比在不同气氛下合成的荧光粉。结果表明,在N2气氛与N2/H2气氛下分别合成的SrSi2O2N2:Eu2+荧光粉物相结构和光谱特性基本一致。显示出合成了主晶相SrSi2O2N2,但还含有少量未知的中间项。Eu2+浓度的变化不影响激发状态,而发射光谱的波长在Eu2+浓度为1mol%-20mol%之间,从530 nm的绿光红移至550 nm的黄绿光区域。同时,激发光谱覆盖的范围宽,均能有效的被UV或蓝光激发,这意味着该类荧光粉在白光LED方面有可能得到广泛的应用。

Preparation and Properties Characterization of SrSi2O2N2:Eu2+ Phosphors

Eu²⁺ doped SrSi₂O₂N₂ phosphors were prepared by the auto-reduction solid-state reaction method using the SrCO₃, Si₃N₄, and Eu₂O₃ as the starting materials under N₂ atmosphere. The structural characterization, luminescence spectra and the crystal morphology of the synthesized phosphors were investigated. The phosphors synthesized under different atmosphere were also analyzed. The X-ray diffraction patterns of synthesized phosphors are indexed to the SrSi₂O₂N₂ phase and an unknown intermediate phase. The shape and position of excitation band are not greatly influenced by the Eu²⁺ concentration. However, a systematic red shift of the emission band is observed as the Eu²⁺ concentration increase form 1mol% to 20mol%, resulting in a green-greenish yellow emission peaking from 530 to 550 nm. Meanwhile, this oxynitride phosphors have a broad excitation band extending form from ultraviolet to visible light rang, enabling them to be used for white light-emitting diodes (LED) when an ultraviolet or blue LED chip is combined.