【摘要】 采用高温固相反应法制备了Sr2SiO4:xEu2+荧光粉,研究Eu2+所占据的Sr2SiO4中Sr1和Sr2两个不同格位及掺杂浓度和激发波长对格位发光的影响。荧光粉发射光谱为一双峰的宽发射光谱,可拟合为峰值位置位于480nm和530nm的两条高斯曲线,分别对应Eu2+所占据的Sr1和Sr2两个不同格位的发射。随着Eu2+掺杂浓度增加,Sr1和Sr2格位的发光强度均出现浓度猝灭现象,Sr2格位的长波长发射峰出现明显红移现象,而Sr1格位的短波长发射峰发生红移-蓝移-红移现象,这与Sr1和Sr2格位的优先占据以及格位间能量传递有关。随着激发波长的增加,Sr2格位的长波长发射的发光强度与Sr1格位的短波长发射的发光强度比值增加,占据不同格位的Eu2+对不同激发波长表现出明显的选择激发效应。更多还原

【Abstract】 Sr2SiO4:xEu2+samples were prepared using a solid-state reaction method.Eu2+activators are located at two different crystallographic sites,namely high energy site and low energy site.The emission band of Sr2-x SiO4:xEu2+is a super-position of two distinct emission peaks at 480nm and 530nm.The luminescence properties of the two different crystallographic Sr2+sites are influenced by Eu2+concentration and excitation wavelength.It is found that the concentration quenching phenomenon is observed at two sites,with the increase of doping concentration.With the decrease of the excitation light energy,the emission intensity ratio of low energy site to high energy site is increasing.It shows that different sites have an obvious selective absorption.The process parameters are also investigated in this paper.更多还原