保温辅助法燃烧合成Ca-α-SiAlON:Eu^(2+)荧光粉

Thermal-Insulation-Assisted Combustion Synthesis of Ca-α-SiAlON:Eu^(2+) Phosphors

采用一种保温辅助(TIA)的燃烧合成工艺,高效、快捷地制备出了高性能Eu^(2+)掺杂的Ca-α-Si Al ON荧光粉。在传统的燃烧合成工艺的基础上,在反应物原料的外部包裹氮化硅保温层,显著阻碍了燃烧过程中的热量散失,使体系处于高温反应区的时间延长至原有工艺的3倍以上,从而促进了晶体的充分生长和发育。通过使用XRD、SEM、PL光谱等测试手段对产物进行全面分析,发现在使用了氮化硅保温层的样品中,产物为纯相的Ca-α-Si Al ON,颗粒的结晶良好,呈现等轴状形貌,粒径分布均匀。PL光谱测试表明,其在250~350 nm和350~450 nm区间内存在2个较宽的吸收带,在568 nm附近处有较强的黄光发射。包裹了氮化硅保温层后,产物的荧光性能有了明显改进,激发光谱和发射光谱的强度均有显著提高。

Eu-doped Ca-α-Si Al ON phosphors were prepared by a newly-developed thermal-insulation-assisted(TIA)combustion synthesis method.With Si_3N_4 powders cladding on the reactant mixtures,the duration of the CS system in the high temperature period is remarkably enhanced due to the low heat dissipation.The as-produced Ca-α-Si Al ON:Eu^(2+)phosphors feature high purity,good uniformity and outstanding luminescence properties with a yellow emission peak at 568 nm under a UV or blue light excitation.The excitation and emission intensities for the as-synthesized phosphors are notably improved with the assisting by Si_3N_4 insulating layer.